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With threshold detection

Subclass of:

323 - Electricity: power supply or regulation systems

323234000 - OUTPUT LEVEL RESPONSIVE

323265000 - Using a three or more terminal semiconductive device as the final control device

323282000 - Switched (e.g., switching regulators)

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Entries
DocumentTitleDate
20110181262SWITCHING REGULATOR - Provided is a switching regulator capable of performing stable start-up with a soft-start operation without causing excessive extension of a soft-start time period. In a start-up period, a voltage approximating a feedback voltage (FB) is provided as an initial value of a soft-start reference voltage. The feedback voltage (FB) and the soft-start reference voltage become substantially equal to each other at a moment when the start-up is completed, to thereby realize a smooth transition of an operating state from the start-up to normal control.07-28-2011
20120161738SWITCHING-MODE POWER SUPPLY DEVICE - Disclosed is a switching-mode power supply device which outputs a voltage having a different electrical potential from an input voltage including an inductor, a driving switching element and a control circuit, and the control circuit includes a trigger signal generating circuit which generates and outputs a signal which provides timing to turn the driving switching element on or off, a first timekeeping unit which times a fixed ON period or a fixed OFF period which defines the pulse width of a driving pulse of the driving switching element, a second timekeeping unit which times a minimum OFF period or a minimum ON period of the driving switching element and a sudden load change detection circuit which detects a sudden load change.06-28-2012
20090085546Fast Transient Step Load Response in a Power Converter - A method of controlling a power converter having at least one switching device for supplying an output voltage and a load current to a load is disclosed. The method includes sensing the output voltage and sensing the load current. The method further includes controlling a duty cycle of the switching device according to the sensed output voltage and a voltage control loop when a rate of change of the load current does not exceed a threshold level. The method also includes adjusting the duty cycle of the switching device set by the voltage control loop when the rate of change of the load current exceeds the threshold level.04-02-2009
20100164458INDUCTIVE POWER SYSTEM - An inductive power transfer system for coupling a power source to a load across an air gap is provided, including a primary unit and a secondary unit separable from the primary unit and arranged to receive power inductively from the primary unit when placed proximate thereto. The system includes a multi stage comparator for monitoring operating conditions within the secondary unit and feedback loop for transmitting a feedback signal to the primary unit when predetermined operating conditions are detected within the secondary unit. The primary unit is arranged to operate in a low power mode where power is applied to the primary winding for a minimal period during each switching cycle when no feedback signal is received and a high power mode where power is applied to the primary winding for the majority of each switching cycle when a feedback signal is received. The power transfer system functions by applying bursts of power from the primary to the secondary unit, the bursts becoming more frequent and of longer duration as the load on the secondary unit increases or the air gap increases, so as to transfer more power or maintain power as air gap losses increase. The bursts of power will also change their duration and frequency in correspondence with variations of the input power supply to the primary unit, so as to maintain the voltage regulation of the power delivered to the secondary unit.07-01-2010
20100164460APPARATUS FOR AUTO-REGULATING INPUT POWER SOURCE OF DRIVER - An apparatus for auto-regulating the input power source of a driver is provided. The apparatus includes a load detector and a controller. The load detector detects a load current and outputs a detection signal according to the load current. The controller is coupled to the load detector and receives the detection signal. The controller provides an operation voltage between a first voltage and a second voltage, wherein the first voltage is lower than the second voltage. The operation voltage is supplied to the driver and regulated flexibly according to different load demand. In the light loading, the device for auto-regulating the input power source can improve the use efficiency of electric power.07-01-2010
20100164457Voltage Regulator Circuit - One embodiment of the invention includes a regulator circuit that regulates a substantially constant magnitude of an output voltage at an output node. The circuit includes a master stage configured to set a first threshold voltage and a second threshold voltage. The first threshold voltage can have a magnitude that is greater than the second threshold voltage. The circuit also includes a charging follower stage configured to conduct a first current from a first power rail to the output node. The first current can increase in response to a transient decrease of the output voltage relative to the first threshold voltage. The circuit further includes a discharging follower stage configured to conduct a second current from the output node to a second power rail. The second current can increase in response to a transient increase of the output voltage relative to the second threshold voltage.07-01-2010
20100164459VOLTAGE LIMITER AND PROTECTION OF A PHOTOVOLTAIC MODULE - A voltage limiter device of an assembly of photovoltaic modules, including: (a) means (Z07-01-2010
20080258698SOFT START CIRCUIT, POWER SUPPY UNIT AND ELECTRIC EQUIPMENT - A soft start circuit includes a constant current source for generating a constant current, a first current mirror circuit for generating from the constant current a first mirror current, a second current mirror circuit for generating from the constant current a second mirror current smaller than the first mirror current, and a capacitor into which a difference between the first mirror current and the second mirror current is introduced, wherein a divided voltage of a charging voltage thereof is output as a soft start voltage. The soft start circuit provides a gradual soft start voltage.10-23-2008
20110193542Thermally Controlled Driver/Switching Regulator, and Methods of Controlling and/or Regulating a Driver and/or Switching Regulator - The present invention provides circuits and methods for regulating and/or controlling integrated circuits such as drivers and switching regulators. The circuit generally includes a first switch configured to control or regulate a current, voltage drop or voltage boost; a first regulator or driver configured to transmit first pulses to the first switch, the pulses having a first pulse width; and pulse width modulation circuitry configured to (i) reduce the first pulse width when a first thermal threshold is met and (ii) increase the first pulse width when a second thermal threshold is met, the second thermal threshold being less than the first thermal threshold.08-11-2011
20100072969System and method for near zero light-load supply current in switching regulator - Techniques for near zero light-load supply current in switching regulators are described. In one aspect a voltage regulator operating a normal mode is generating an error signal indicating a difference between the output and the regulated voltage. A control signal, at least in part based on the error signal, actively controls the output of the regulator. The control signal is monitored over period of time. The monitoring activates a signal indicating when the control signal is inactive for the period of time indicating a light-load condition. The voltage regulator is then placed in a standby mode when the signal is active and the error signal indicates the output is substantially at the regulated voltage. Portions of the voltage regulator are then disabled permitting the voltage regulator to operate at the minimum current draw.03-25-2010
20100072967CONVERTER CONTROL CIRCUIT - There is provided a converter control circuit including: a high-side switching element connected between an input voltage terminal and an inductive load; a low-side switching element connected between the inductive load and a reference potential; a drive circuit configured to drive a gate of the switching elements; a drive switch connected to the gate of at least one of the switching elements in parallel with the drive circuit; and a drive switch control circuit switching the drive switch from ON to OFF when the gate voltage of the switching element with the gate connected to the drive switch reaches a prescribed threshold while the switching element is driven by the drive circuit.03-25-2010
20100072966CIRCUIT WITH ISOLATION INTERFACE AND REMOTE ON/OFF - A circuit with an isolation interface and a remote on/off function is disclosed. The circuit includes a controller included in a primary side of the circuit. The controller is coupled to receive a primary side feedback signal and the controller is configured to enter a shutdown mode when the primary side feedback signal exceeds a feedback signal threshold. The circuit also includes an isolation interface coupled to galvanically isolate the primary side from a secondary side of the circuit. The isolation interface translates a secondary side feedback signal from the secondary side into the primary side feedback signal on the primary side. The isolation interface is configured to adjust the primary side feedback signal to exceed the feedback signal threshold in response to an on/off signal.03-25-2010
20130076326DUAL-MODE SWITCHING REGULATOR - There is provided a dual-mode switching regulator including: a comparison unit comparing an input voltage input through an input terminal with a pre-set reference voltage and outputting a comparison result signal; a switching signal generation unit generating a regulator selection signal for controlling a previously connected regulator path and a bypass selection signal for controlling a previously connected bypass path according to the comparison result signal; a regulator included in the regulator path and converting the input voltage to a pre-set voltage; a regulator path selection unit switching the regulator path including the regulator between the input terminal and an output terminal on or off, according to the regulator selection signal; and a bypass path selection unit switching the bypass path connecting the input terminal and the output terminal without passing through the regulator on or off, according to the bypass selection signal.03-28-2013
20130043855POWER SUPPLY DEVICE AND METHOD THEREOF - A power supply device generating an output voltage and including a first switching module, a second switching module, a detection module, a pulse width modulation (PWM) module and an energy storage filter module is disclosed. The first switching module is coupled between a first voltage source and a switching node. The second switching module is coupled between the switching node and a second voltage source. The detection module detects voltage of the switching node. The PWM module generates a first PWM signal and transmits the first PWM signal to the first switching module according to a detection result of the detection module. The energy storage filter module processes the voltage of the switching node to generate the output voltage.02-21-2013
20130043854ADJUSTABLE RESONANT BUCK CONVERTER - A power converter includes first and second circuit modules, a first capacitor, a second diode and a control module. The first circuit module includes a switching element in parallel with a first diode. The second circuit module includes a first inductor and the first circuit module. The inductor is in series with the first circuit module. The first capacitor is in parallel with the second circuit module. The second diode includes a first terminal and a second terminal, where the first terminal is in series with the second circuit module and the first capacitor, and the second terminal is coupled to a second power terminal. The control module varies one or more of the first capacitor and the first inductor based on at least one of a current of a load circuit or an input voltage. A resonating waveform is generated by a resonant circuit of the second circuit and is used by the control module to turn off the switching element under zero-current and zero-voltage conditions.02-21-2013
20100045255Voltage Generator Arrangement and Method for Voltage Conversion - A voltage generator arrangement which comprises a voltage converter (02-25-2010
20130038309VOLTAGE REGULATOR CIRCUIT - One embodiment of the invention includes a regulator circuit that regulates a substantially constant magnitude of an output voltage at an output node. The circuit includes a master stage configured to set a first threshold voltage and a second threshold voltage. The first threshold voltage can have a magnitude that is greater than the second threshold voltage. The circuit also includes a charging follower stage configured to conduct a first current from a first power rail to the output node. The first current can increase in response to a transient decrease of the output voltage relative to the first threshold voltage. The circuit further includes a discharging follower stage configured to conduct a second current from the output node to a second power rail. The second current can increase in response to a transient increase of the output voltage relative to the second threshold voltage.02-14-2013
20090153122DROPPER-TYPE REGULATOR - A dropper-type regulator capable of providing a soft start function using a simple circuit configuration. An exemplary regulator includes a first FET having a relatively high current driving capability and a second FET having a relatively low current driving capability are provided in parallel between an input terminal and an output terminal. For a predetermined time immediately after power activation, only the second FET is driven, thereby preventing a large rush current. A switch circuit connected to the gate of the first FET is operated after the predetermined period of time, thereby supplying a driving voltage to the gate of the first FET.06-18-2009
20090243579DCDC CONVERTER WITH SOFT-STARTUP AND SOFT-TRANSITION FOR ADJUSTABLE OUTPUT VOLTAGE - A method and exemplary apparatus that incorporate soft-start circuit together with adjustable output voltage control are introduced. By implementing a gradual increment of voltage steps/fast decrement, it can totally eliminate overshoot and limit in-rush current significantly at the initial startup and output voltage transition that happens after startup.10-01-2009
20120182004POWER SUPPLY CONTROLLER - A power supply controller includes a switch circuit to be provided between the power source and power supply path, the switch circuit switches the power supply from the power source to the load between on and off, and a power-supply-path protection circuit. The power-supply-path protection circuit controls switching operation of the switch circuit according to a power-supply command signal that commands to start or terminate the power supply to the load, to calculate a temperature of the power-supply path, and if the calculated temperature reaches a predetermined upper limit, to inhibit the switch circuit from the power supply, thereby protecting the power-supply path. In a case where the power supply by the switch circuit is inhibited, if the temperature of the power supply path decreases to a predetermined threshold temperature, the power-supply-path protection circuit removes inhibition of the power supply by the switch circuit.07-19-2012
20130069611Multi-phase synthetic ripple power converter - A novel method to operate synthetic ripple multi-phase switching power converters at constant frequency is presented. The method includes the means for sensing the current in each phase without adding extra dissipation and for balancing the currents by affecting the synthetic ripple signal to modulate the duty cycle without disturbing the overall output voltage regulation.03-21-2013
20130069613DC/DC CONVERTER - In a DC/DC converter, a control circuit determines an upper limit value of an inductor current based on a load current and an input dc voltage, and changes at least one of an on time and an off time of a switching element in such a manner that the detected inductor current does not exceed the upper limit value.03-21-2013
20130069612Driving an Electronic Switch - An electronic switch is connected in series with a load dependent on an input signal. The electronic switch is operated in a first operation mode for a first time period after a signal level of the input signal has changed from an off-level to an on-level. The first operation mode includes driving the electronic switch dependent on a voltage across the load and dependent on a temperature of the electronic switch. The electronic switch is operated in a second operation mode after the first time period. The second operation mode includes driving the electronic switch dependent on the temperature according to a hysteresis curve.03-21-2013
20090302819Circuit for Preventing Reverse Current and Method thereof - A circuit for preventing a reverse current is applicable to a voltage converter including a high-side switch, a low-side switch, and an inductor. The high-side and low-side switches are coupled in series between two power lines. The inductor is coupled between an output terminal of the voltage converter and a connection node connecting the high-side and low-side switches. The reverse current flows from the output terminal of the voltage converter to the connection node. The circuit includes a first detection module and a threshold voltage adjusting module. The first detection module detects whether the reverse current occurs within a dead time when both the high-side and low-side switches are off. The voltage adjusting module adjusts a crossing voltage according to whether the reverse current is detected. The low-side switch is turned off when the voltage of the connection node exceeds the crossing voltage.12-10-2009
20090302818Power Supply Device and Control Method of the Same - It is determined that a periodic zero current stagnation state is reached to correct a voltage command of a smoothing capacitor downward by a predetermined voltage when a state where a current (reactor current) flowing through a coil in a dead time when switching elements are both off immediately after the switching element (upper arm) is turned off from on stagnates at a value of 0 occurs at switching periods of the switching elements. This can prevent a voltage of the smoothing capacitor from becoming unexpectedly higher than the voltage command in the current stagnation state, prevent the smoothing capacitor from being damaged by an overvoltage and prevent excessive torque from being output from motors.12-10-2009
20090091309OFF-LINE CONVERTER WITH DIGITAL CONTROL - A regulation circuit for use in DC to DC converter is disclosed. One such regulation circuit includes a feedback circuit to be coupled an energy transfer element output to receive a feedback signal to indicate whether the energy transfer element output is above or below a threshold level. A control circuit is included that is to be coupled to a switch that is coupled to an energy transfer element input. The control circuit is further coupled to the feedback circuit to generate a drive signal to control the switch to regulate the energy transfer element output to approximately the threshold level. The control circuit is to maintain an on-time of a current cycle of the drive signal and not allow an on-time of a next cycle of the drive signal in response to the energy transfer element output rising above the threshold level.04-09-2009
20090295356Output ripple control circuit and method for a PWM system - An output ripple control circuit and method for a PWM system uses a hysteresis threshold to clamp the output ripple of the PWM system such that the output ripple will not vary with the dc level of the output voltage, and therefore the output ripple control may be combined into any main loop technologies.12-03-2009
20090267583Switching power supply apparatus with current output limit - A switching power supply apparatus with current output limit, which utilizes a voltage sampling controller for sampling the feedback voltage to acquire a knee voltage. Moreover, the knee voltage is computed by the square-root operation and error elimination operation respectively. According to the result of the computing, the switching of the power switch is controlled so as to stabilize the output voltage and limit the output current.10-29-2009
20110037448Switching regulator with transient control function and control circuit and method therefor - The present invention discloses a switching regulator with transient control function, and a control circuit and a method for controlling the switching regulator. The switching regulator with transient control function includes: a power conversion circuit for receiving an input voltage and converting the input voltage to an output voltage; a feedback circuit for detecting the output voltage and generating a feedback signal representing the output voltage; an output capacitor coupled to an output terminal of the power conversion circuit; and a control circuit for receiving the feedback signal and generating a control signal to control the conversion operation by the power conversion circuit accordingly, wherein the control circuit includes a voltage balancing circuit which discharges the output capacitor when the output voltage is higher than a first predetermined threshold, and charges the output capacitor when the output voltage is lower than a second predetermined threshold.02-17-2011
20130063115CONSTANT-VOLTAGE POWER SUPPLY CIRCUIT - A constant-voltage power supply circuit includes a first transistor connected between a power supply terminal and an output terminal. The constant-voltage power supply circuit includes a voltage divider circuit including a first resistor having a first end connected to the output terminal and a second resistor having a first end connected to a second end of the first resistor and a second end connected to ground. The constant-voltage power supply circuit includes an output voltage control amplifier that compares the divided voltage and a reference voltage and controls a voltage of a control terminal of the first transistor. The constant-voltage power supply circuit includes a current-limiting characteristic control circuit that controls the voltage of the control terminal of the first transistor according to the divided voltage and an output current.03-14-2013
20130063116TRUE REVERSE CURRENT BLOCKING SYSTEM - Devices, systems and methods are provided for a switch to perform true reverse current blocking (TRCB). The device may include a PMOS switch, including a source port, a drain port, a gate port and an n-well region; an input voltage port coupled to the source port; an output voltage port coupled to the drain port; a switch control port coupled to the gate port; and comparator circuitry configured to compare an input voltage at the input voltage port with an output voltage at the output voltage port and select a maximum of the input voltage and the output voltage. The comparator circuitry may be further configured to couple the selected maximum to the n-well region.03-14-2013
20090237056Transient Processing Mechanism for Power Converters - Transient processing mechanisms for power converters. Error generation circuitry in a power converter may generate an error signal based on the difference between a power converter output voltage and a reference voltage. Transient detection circuitry may detect whether the error signal exceeds at least a first threshold. If the first threshold is exceeded, timing control logic may generate a low band correction pulse to adjust the power converter output voltage, and thereby adjust the error signal to a level within the first threshold. If the error signal exceeds a second threshold, the timing control logic may generate a high band correction pulse to adjust the power converter output voltage, and thereby adjust the error signal to a level within the second threshold. The timing control logic may initiate a low band blanking period following the low band correction pulse and high band blanking period following the high band correction pulse.09-24-2009
20090237055POWER SUPPLY DEVICE CAPABLE OF STABLY SUPPLYING OUTPUT VOLTAGE WITH INCREASED RESPONSIVENESS - In a power supply device, a synchronous rectifier step-down converter alternately turns on and off a switch and a synchronous rectifier switch. A reference voltage generator generates a predetermined reference voltage. An error amplifier outputs an error voltage such that an output voltage of the step-down converter approaches the predetermined reference voltage. A pulse-width signal generator generates a pulse-width signal controlling turning on and off the switch and the synchronous rectifier switch based on the error voltage. A driver circuit controls turning on and off the switch and the synchronous rectifier switch based on the pulse-width signal. An inductor is connected in series with output of the step-down converter. A bypass switch short-circuits an output terminal of the step-down converter to an input terminal of the step-down converter. A mode controller controls turning on and off the bypass switch.09-24-2009
20110018516DC-DC CONVERTERS - Methods and apparatus for control of DC-DC converters. The DC-DC converter is operable so that the low side supply switch may be inhibited from turning on in a cycle following the high side supply switch turning off. Turn on of the low side switch is inhibited if the time between turn off of the high side switch and the inductor (L) current reaching zero is less than a predetermined duration. Inhibiting the low side switch from turning on can prevent the inductor current from going negative, which would reduce the efficiency of the converter. When turn on of the low side switch is inhibited the inductor current flows through a parallel path, such as a parasitic body diode associated with the low side switch, which allows current flow in one direction only.01-27-2011
20110018515DC-DC CONVERTERS - Apparatus and method for providing current limiting in a DC-DC converter and especially to methods and apparatus suitable for a start-up mode of operation. The invention monitors the inductor (L) current when the high side supply switch is on against a peak current limit threshold. If the inductor current reaches the peak current limit threshold the high side switch is turned off. The inductor current when the low side switch is off is monitored against a valley current threshold. As long as the inductor current is above the valley current threshold turn on of the low side switch is inhibited. In this way current limiting is provided and the problems of stair-stepping are avoided. Embodiments employing lossless current sensing are described. The invention may be implemented in a start-up mode of operation wherein the converter is controlled purely by the peak current limit and valley current threshold which are increased over time.01-27-2011
20120235661Controlling a Current Between a Source and a Load - A method for controlling a current between an energy source and a load is disclosed. A switching module is coupled between the energy source and the load. The switching module includes two input terminals coupled to the energy source and two output terminals coupled to the load and at least one semiconductor switching element coupled between one of the input terminals and one of the output terminals. At least one current parameter of the current is measured between the energy source and the load. The current between the energy source and the load is interrupted by switching off the switching element when the at least one current parameter reaches or exceeds at least one predetermined parameter threshold value.09-20-2012
20110025286Control Circuit For a Primary Controlled Switched Mode Power Supply with Improved Accuracy of the Voltage Control and Primary Controlled Switched Mode Power Supply - The invention under consideration refers to a controller for a primary-side regulated control power supply unit for the regulation of the output of the primary regulated control power supply unit. The invention also concerns a method for the operation of a control power supply unit of the generic type and a pertinent control power supply unit. The controller comprises a control output (B), which can be connected with the control input of a primary-side switch (Q02-03-2011
20110025285POWER SUPPLY VOLTAGE CONTROLLING CIRCUIT FOR USE IN SUBTHRESHOLD DIGITAL CMOS CIRCUIT INCLUDING MINUTE CURRENT GENERATOR AND CONTROLLED OUTPUT VOLTAGE GENERATOR CIRCUIT - In a circuit and method for correcting a delay variation of a subthreshold CMOS circuit operating in a subthreshold region, a power supply voltage controlling circuit is provided for supplying a controlled output voltage to a subthreshold digital CMOS circuit as a controlled power supply voltage. The subthreshold digital CMOS circuit includes CMOS circuits each having a pMOSFET and an nMOSFET and operating in a subthreshold region with a predetermined delay time, and further includes a minute current generator circuit generating a predetermined minute current based on a power supply voltage, and a controlled output voltage generator circuit generating a controlled output voltage for correcting a variation in the delay time based on a generated minute current and supplying the controlled output voltage to the subthreshold digital CMOS circuit as a controlled power supply voltage including a change in each threshold voltage of the pMOSFET and the nMOSFET.02-03-2011
20120286757Load Adaptive Loop Based Voltage Source - Systems and methods are provided for a power supply. A first output stage is configured to supply power from a power source at a target voltage to a device in an integrated circuit in response to a power demand of the device. Load detector circuitry is configured to detect a load resulting from operation of the device, and a supplemental output stage is configured to selectively supply supplemental power from the power source to the device, in addition to the power provided by the first output stage, in response to detection of an additional load resulting from operation of the device.11-15-2012
20120286756CONTROL CIRCUIT FOR STEP-UP SWITCHING REGULATOR - A switching transistor is arranged between a switching (SW) terminal and the ground terminal. An error amplifier amplifies the difference between the feedback voltage V11-15-2012
20120286754CURRENT PROVIDING METHOD AND CURRENT PROVIDING SYSTEM - A current providing method utilized to a power supplying circuit, which provides an output current to a loading. The current providing method comprising: detecting if a current value of the output current is larger than a threshold current value; computing a number that the current value of the output current is larger than the threshold current value; determining if the number is larger or equal to a predetermined number; and controlling the power supplying circuit to decrease the output current to a predetermined current value if the number is larger or equal to the predetermined number.11-15-2012
20110031950System and Method for Load Control - A system is described including a means for receiving a potential and selectively supplying the potential to a load. The receiving and supplying means being responsive to a load control signal to supply the potential to the load when the load control signal is present. The system also includes a means for measuring a load demand. Also included is a means for controlling the receiving and supplying means. The controlling means continuously providing the load control signal when the load demand is greater than a predetermined threshold. The controlling means temporarily providing the load control signal to determine the load demand when the load demand is less than the predetermined threshold.02-10-2011
20110291633Current Source Arrangement, Circuit Arrangement with the Current Source Arrangement and Method for Operating Such an Arrangement - In one embodiment, the current source arrangement comprises a current source (B), that has two output terminals (12-01-2011
20120098513SEMICONDUCTOR INTEGRATED CIRCUIT FOR REGULATOR - A regulator includes a transistor connected between an input and an output. A feedback voltage controls the transistor to keep the output voltage constant. A first circuit functions as a comparator to compare a detection voltage from the output of the transistor and the feedback voltage when the output current is higher than a predetermined value, and functions as a buffer when the output current is lower than the predetermined value. A second circuit receives a reference voltage, the feedback voltage, and an output from the first circuit, and generates (i) a difference between the feedback voltage and the first circuit output when the reference voltage is lower than the first circuit output, and (ii) a difference voltage between the feedback voltage and the reference voltage when the reference voltage is higher than the first circuit output, and supplies a control voltage to control the output of the transistor.04-26-2012
20120098512ELECTRONIC DEVICE AND METHOD FOR DC-DC CONVERSION - An electronic device for DC-DC conversion including a feedback loop coupled at one side to the inductor for measuring a current through the inductor with a series of an auxiliary capacitor and an auxiliary resistor, a transconductance stage coupled to the auxiliary capacitor for generating a current proportional to a voltage drop across the auxiliary capacitor, wherein the electronic device further includes a ramp resistor coupled to the output of the transconductance stage for generating a ramp voltage across the ramp resistor and a comparator receiving at a first input the ramp voltage, wherein the output of the comparator is coupled to a gate driving stage for driving a power transistor coupled with a control gate to the gate driving stage and with a channel to a switching node of the electronic device.04-26-2012
20100090673POWER SUPPLY APPARATUS AND POWER SUPPLY METHOD - A power supply apparatus is provided which includes: a first switch provided between an inductor and a terminal to which a reference voltage is applied; a second switch provided between the inductor and an output terminal; a first comparator circuit that compares an input voltage with a first comparison voltage; a signal generating circuit that outputs a frequency signal according to an output from the first comparator circuit; and a first control circuit that controls the first and second switches based on an output from the signal generating circuit to control an electrical current flowing into the inductor.04-15-2010
20090273328VOLTAGE/CURRENT CONTROL APPARATUS AND METHOD - A voltage/current control apparatus and method are disclosed. The apparatus includes a low-side field effect transistor (FET) having a source, a gate and a drain, a high-side field effect transistor (FET) having a source, a gate and a drain, a gate driver integrated circuit (IC), a sample and hold circuit, and a comparator configured to produce a trigger signal at the output when a sum of the first and second input signals is equal to a sum of the third and fourth input signals, wherein the trigger signal is configured to trigger a beginning of a new cycle by turning the gate of the high-side FET “on” and the gate of the low-side FET “off”.11-05-2009
20100033150BUS VOLTAGE OPTIMIZER FOR SWITCHED POWER CONVERTER - Methods, systems, and devices are provided for optimizing a bus voltage supplied to a switching power converter to keep the duty cycle of the switching power converter to within a desirable operating range. In some embodiments, the duty cycle of the switching signal used to drive the switching power converter is monitored (e.g., indirectly) to determine whether the duty cycle is approaching an undesirable level. For example, as the duty cycle decreases (e.g., approaches or crosses a certain threshold), embodiments decrease the bus voltage. This may, in turn, allow the switching power converter to output substantially the same output to the load, while using a more efficient (e.g., larger) duty cycle. Certain embodiments use similar techniques, along with certain bus voltage optimization techniques, to control a bus voltage as a function of feedback from multiple switching power converters.02-11-2010
20110215782Power regulator and controlling method thereof - Methods and circuits related to power regulation are disclosed. In one embodiment, a power regulator for converting an input electrical signal to an output electrical signal to supply power to a load, can include: (i) a power stage having switching devices and a filter; (ii) a regulation signal generator for the switching devices that includes a feedback circuit and a PWM, the feedback circuit receiving an output signal from the power stage, the PWM receiving an output from the feedback circuit, and generating a PWM control signal; (iii) a constant time generator receiving the PWM control signal and generating a constant time signal based on the PWM control signal duty cycle; and (iv) a logic/driving circuit receiving the PWM control signal and the constant time signal, and controlling operation of the switching devices to modulate the output signal from the power stage, and maintaining a pseudo constant operation frequency.09-08-2011
20090189584VOLTAGE REGULATOR - Provided is a voltage regulator capable of reducing fluctuation of an output current even when an output terminal thereof is short-circuited. In a case where the output terminal of the voltage regulator is short-circuited, an output current (Iout) of the voltage regulator is limited and fixed to a limit current value. When an output voltage (Vout) of the voltage regulator decreases to have a value equal to or smaller than not a detection voltage value (Vref07-30-2009
20100072968CONTROL SYSTEM FOR SWITCHING DC-DC CONVERTERS - A control system for a switching DC-DC converter is proposed. The converter includes an input terminal for receiving an input voltage from a source, a control terminal adapted to receive a switching control signal, and an output terminal for providing to a load an output voltage generated from the input voltage according to the control signal. The control system includes detecting means for detecting a reaching condition of a predetermined value by a current provided to the load by the converter and control means for controlling the control signal according to the output voltage. The control system further includes disabling means for disabling the supply of the control signal to the control terminal according to the detection of the reaching condition. The disabling means includes selection means for controlling the disabling according to a time relationship between the detection of the reaching condition and the control signal.03-25-2010
20100237844REFERENCE VOLTAGE PROVIDING CIRCUIT AND RELATED METHOD - A reference voltage providing circuit, for providing a reference voltage to an error amplifier comparing the reference voltage and a feedback voltage. The reference voltage providing circuit comprises: a voltage detection module, for detecting the feedback voltage to generate a control signal; and a controllable voltage providing module, for providing the reference voltage according to the control signal.09-23-2010
20110080149POWER CONVERSION CONTROL APPARATUS - The power conversion control apparatus is for controlling a power conversion circuit in which a plurality of pairs each including a high-side switching element and a low-side switching element connected in series to each other are connected in parallel to a capacitor, and an external battery is connected to the capacitor through a relay. To discharge the capacitor, the power conversion control apparatus turns on both the high-side and low-side switching elements of at least one of the pairs to make a short circuit between both electrodes of the capacitor on condition that the relay is open.04-07-2011
20100123445SWITCHING CIRCUIT AND SMALL-SIZE HIGH-EFFICIENCY DC-DC CONVERTER FOR PORTABLE DEVICES INCLUDING THE SAME - Provided are a switching circuit and a small-size high-efficiency direct current-to-direct current (DC-DC) converter for portable devices including the same. Using dynamic threshold-complementary metal oxide semiconductor (DT-CMOS) transistors having dynamic threshold voltages as a switching device, the switching circuit maintains a low threshold voltage in a normal mode to improve current drivability while reducing conduction loss, and maintains a high threshold voltage in a standby mode to minimize power consumption. When the switching circuit is employed in a DC-DC converter, power conversion efficiency can be improved by reducing conduction loss in the normal mode, and power consumption can be minimized in the standby mode. Consequently, the DC-DC converter can maximize a use time of a battery of a portable device and can be useful in power supplies of portable devices that are gradually being miniaturized.05-20-2010
20090146631STEP-DOWN SWITCHING REGULATOR - In a control circuit which turns on/off the switching device elements included in a synchronous rectifier step-down switching regulator, a hysteresis comparator compares the detection voltage that corresponds to the output voltage of the step-down switching regulator with a first threshold voltage and a second threshold voltage. A light-load detection circuit detects whether or not a load is in the light-load state. A driver circuit turns on/off the switching device elements according to the pulse signal output from the hysteresis comparator. Upon the light-load detection circuit detecting the light-load state, the hysteresis comparator shifts the second threshold voltage toward the higher-voltage side by a predetermined voltage difference.06-11-2009
20080290854Switching regulator having reverse current detector - A switching regulator includes first and second transistors, which are provided in series between power sources respectively having first and second potentials, and which convert a direct current voltage of a potential difference between the first and the second potentials into an alternating current voltage, and a control circuit. The control circuit includes a comparator which compares the alternating current voltage and a threshold voltage in a period when the second transistor is to be on, and receives a predetermined voltage, at least immediately before the period in which the second transistor is to be on, the predetermined voltage being farther than a midpoint potential of the first and second potentials from the threshold voltage. The control circuit performs control such that the second transistor becomes turned off, when the comparator judges that the alternating current voltage has exceeded the threshold voltage toward the midpoint potential direction, in the period when the second transistor is to be on.11-27-2008
20100123444ACCELERATED RESPONSE TO LOAD TRANSIENTS IN PFM DC-TO-DC CONVERTERS - A pulse generator circuit in a DC-to-DC converter may be configured to generate pulses that have a frequency that increases in response to increases in the load on the DC-to-DC converter. The pulse generator circuit may be configured to cause each pulse to have a constant width. When the pulse reaches the end of the constant width and the magnitude of the current through an inductance in the converter is less than a threshold value, however, the pulse generator may be configured to extend the pulse until the magnitude of the current through the inductance reaches the threshold value. The pulse generator circuit may be configured to prematurely terminate each pulse if and at such time as the load voltage exceeds a target value by approximately half of the peak-to-peak voltage of the ripple component plus the noise component margin.05-20-2010
20100085028SYSTEM AND METHOD FOR PROVIDING LINEAR BUCK BOOST TRANSITIONS WITHIN A BUCK BOOST CONVERTER - A voltage regulator, comprises first circuitry for generating an output voltage responsive to an input voltage and a plurality of switching control signal. Switching control circuitry generates the switching control signals responsive to the output voltage and at least one of a buck ramp signal and a boost ramp signal. Voltage ramp generation circuitry generates each of the buck ramp signal and the boost ramp signal. The boost ramp signal comprises the buck ramp signal offset by the peak value of the buck ramp signal.04-08-2010
20080203989Voltage Converter Apparatus and Method Therfor - In the field of step-down voltage conversion, it is known to regulate an output of a DC-DC converter circuit with both a Pulse Wave Modulation voltage signal or a Pulse Frequency Modulation voltage signal, depending upon a current demand made upon the DC-DC converter circuit. Typically, circuits to generate both voltage signals are provided and selection of the appropriate regulation mode is achieved by means of a pin and decision software controlling the pin. However, the use of the pin and the software is an overhead that is desirably avoided. Consequently, the present invention provides a voltage conversion apparatus comprising a signal analyser to analyse a load current signal and compare a characteristic of the load current signal to at least one predetermined criterion. Regulation by the PWM signal or the PFM signal is selected in response to the evaluation of the comparison with the at least one criterion.08-28-2008
20110062930VARYING OPERATION OF A VOLTAGE REGULATOR, AND COMPONENTS THEREOF, BASED UPON LOAD CONDITIONS - A method for operating a voltage regulator controller, for use in a voltage regulator including coupled inductors, is provided as follows. A first signal is generated for driving a first switch of the voltage regulator. A second signal is generated driving a first switch of the voltage regulator. The voltage regulator determines whether a light-load condition exists. Upon determining the existence of a light-load condition, adjusting the phase difference between said first and second signals so that the first and second signals are approximately in-phase.03-17-2011
20110062929FEEDBACK CONTROL OF A DC/DC POWER CONVERTER - A current mode power conversion system and method are described that provide a stable output voltage and a maximum-limited output current to a load. The system comprises: 03-17-2011
20090295354LOW POWER ONE-SHOT BOOST CIRCUIT - This invention discloses a voltage boost circuit which comprise at least one capacitor with a first terminal connected to an output of the voltage boost circuit, a controllable switch connected between a second terminal of the capacitor and a voltage source, the second terminal being different from the first terminal, and a voltage level detector detecting the output voltage level of the voltage boost circuit and providing a control signal to the controllable switch, wherein when the output voltage exceeds a predetermined level the controllable switch is off, and when the output voltage is lower than the predetermined level the controllable switch is on.12-03-2009
20090206814METHOD AND SYSTEM FOR EFFICIENT POWER CONTROL WITH MULTIPLE MODES - Method and system for efficient power control with multiple modes. According to an embodiment, the present invention provides a power system with selectable power modes. The power system includes a first terminal for outputting energy, and the first terminal is electrically coupled to a load. The system also includes a pulse-frequency modulation (PFM) component that is configured to adjust a pulse frequency based on the load. The system additionally includes a pulse-width modulation (PWM) component that is configured to adjust a pulse width based on the load. The system further includes a switch that is electrically coupled to the first terminal. Also, the system includes a control component, the control component being configured to provide a control signal that is capable of causing the switch to be turned on or off. The control signal is associated with an output of the PWM component and the pulse width if an output is greater than a predetermined value. The control signal is associated with an output of the PFM component and the pulse frequency if an output is lower than a predetermined value.08-20-2009
20090273329STEP-DOWN TYPE SWITCHING REGULATOR - A pulse signal generating circuit generates a pulse signal having a duty ratio controlled such that the output voltage approaches a reference voltage. A driver circuit generates first and second gate voltages, which are to be respectively applied to the gates of a switching transistor and a synchronous rectifier transistor, based upon the pulse signal. A threshold voltage generating unit generates a threshold voltage which is synchronous with the second gate voltage, and which is in the high-level state during a period when the synchronous rectifier transistor is to be turned off and in the low-level state during a period when the synchronous rectifier transistor is to be turned on. A light-load detection comparator compares a switching voltage with the threshold voltage, and outputs a light-load detection signal.11-05-2009
20090295355Voltage converting device and voltage converting method - A changing-speed calculator monitors a current value of an output current flowing through a load circuit to calculate a change speed of the current value. A correction-amount obtaining unit reads from a correction-amount table a correction amount of a duty ratio corresponding to the change speed of the output current. A reference-voltage comparator compares a voltage value of an output voltage to be applied to the load circuit and a predetermined reference voltage with each other, and then notifies a duty-ratio determining unit of the comparison result. The duty-ratio determining unit performs feedback control according to the comparison result of the voltage values to correct the duty ratio. After correcting the duty ratio, the duty-ratio determining unit further corrects the duty ratio by the correction amount obtained by the correction-amount obtaining unit.12-03-2009
20090295353DIFFERENTIAL CURRENT SENSOR DEVICE AND METHOD - A current sensor having a pair of sense transistors is disclosed. The sense transistors sense a current conducted by a power transistor of a voltage regulator. The ratio in size between the power transistor and the sense transistors corresponds to a scaling factor M. Each sense transistor has an associated series connected sense resistor. The two sense resistors are unbalanced and provide a differential voltage based on the sensed current at the sense transistor to a transconductor. The transconductor has heavy emitter degeneration to provide an output current substantially proportional to the current conducted by the primary power transistor, the proportion determined by the scaling factor M and a ratio of the emitter degeneration and sense resistors.12-03-2009
20110267020METHOD AND MEANS TO IMPLEMENT FIXED FREQUENCY OPERATION OF BUCK MODE SWITCHING - A buck mode switching power supply under hysteretic control is provided. A fixed frequency pattern generator is operatively connected to the supply and configured to provide dynamic adjustment of the hysteretic threshold voltage level, resulting in the fixed frequency operation of the supply.11-03-2011
20080238396Feedback controller having multiple feedback paths - A feedback controller comprises first and second feedback circuits. The first feedback circuit is connected between an input node and an output node and has an error node. The first feedback circuit comprising a feedback amplifier for comparing a feedback signal to a reference signal and providing an error signal, and a comparator for comparing the error signal to a second reference signal and providing an output signal. The second feedback circuit is connected between the input node and the error node and comprises a current source coupled to the error node and a controller coupled to the input node for controlling the current source in response to a value of the feedback signal being above or below a threshold value.10-02-2008
20130021014METHOD AND APPARATUS FOR IMPLEMENTING SLEW RATE CONTROL USING BYPASS CAPACITOR - An example circuit includes a capacitance circuit coupled between a first node and a second node. A regulator circuit is coupled to the capacitance circuit to regulate a supply voltage across the capacitance circuit with a charge current during a normal operation mode of the circuit. A slew rate control circuit is coupled to the capacitance circuit and the regulator circuit. The slew rate control circuit is coupled to set a slew rate of a change in voltage over change in time between the first and second nodes during a power up mode of the circuit. The slew rate control circuit includes a transistor coupled between the first and second nodes to shunt excess current from the charge current.01-24-2013
20080284402Power Supply Unit and Portable Apparatus Using the Same - A power supply unit comprises a series regulator and a switching DC-DC converter controlled by a PWM signal and connected in parallel with the series regulator, which are switchably enabled by a mode instruction signal depending on the magnitude of a load current. In switching the series regulator and the DC-DC converter, they are simultaneously enabled for a predetermined overlapping time. Further, in changing the operating condition of the DC-DC converter, the width of the PWM signal is shortened to extend the dead time of the DC-DC converter by a predetermined period, thereby suppressing free oscillations and accompanying overshoots that could take place in the power supply unit during switching.11-20-2008
20090079409VOLTAGE/CURRENT CONTROL APPARATUS AND METHOD - A voltage/current control apparatus and method are disclosed. The apparatus includes a low-side field effect transistor (FET) having a source, a gate and a drain, a high-side field effect transistor (FET) having a source, a gate and a drain, a gate driver integrated circuit (IC), a sample and hold circuit, and a comparator configured to produce a trigger signal at the output when a sum of the first and second input signals is equal to a sum of the third and fourth input signals, wherein the trigger signal is configured to trigger a beginning of a new cycle by turning the gate of the high-side FET “on” and the gate of the low-side FET “off”.03-26-2009
20100289474CONTROLLERS FOR CONTROLLING POWER CONVERTERS - In one embodiment, a controller includes a first comparator, a second comparator and a control unit coupled to the first and second comparators. The first comparator is operable for comparing a first sense signal indicative of an output current flowing through an energy storage component of the power converter with a first threshold, and for generating a first comparison signal. The second comparator is operable for comparing a second sense signal indicative of the output current with a second threshold and for generating a second comparison signal. The control unit is operable for turning a switch of the power convertor on and off according to the first and second comparison signals. The energy storage component is coupled to a power source for storing energy from the power source if the switch is turned on, and is decoupled from the power source for releasing stored energy to a load if the switch is turned off.11-18-2010
20110204866SWITCH CONTROL DEVICE, POWER SUPPLY DEVICE INCLUDING THE SAME, AND SWITCH CONTROL METHOD - The present invention relates to a switch control device, a power supply device, and a switch control method. A switch control device controls a switching operation of a power switch by using a feedback voltage of an output voltage. In detail, the switch control device generates the feedback current according to the feedback voltage and the feedback signal corresponding to the feedback voltage by using the feedback current. The switch control device compares the sensing signal corresponding to the drain current flowing to the power switch and the feedback signal, and turns off the power switch according to the comparison result. The switch control device increases the feedback gain rather than the feedback current during the gain compensation period after a predetermined gain compensation period, and the gain compensation period is longer than a soft start period in which the output voltage is gradually increased.08-25-2011
20080211474Step-up/down DC-DC converter - A step-up/down DC-DC converter is disclosed that includes: a step-up/down part generating an output voltage by stepping up or down an input voltage; and a control part generating an error signal indicating an error between a voltage value obtained by dividing the output voltage and a predetermined reference voltage, and causing the step-up/down part to perform a step-up or step-down operation based on the comparison between the error signal and first and second triangle wave signals. The control part includes a first circuit generating the first triangle wave signal for step-down control and a second circuit generating the second triangle wave signal for step-up control. The first circuit generates a clock signal synchronized with the first triangle wave signal, and outputs the clock signal to the second circuit. The second circuit generates the second triangle wave signal synchronized with the first triangle wave signal based on the input clock signal.09-04-2008
20100201335OFF TIME CONTROL METHOD FOR SWITCHING REGULATOR - The present invention provides an off time control method and switching regulator using it. The current flowing through a switch is compared with a current threshold, and the switch is turned off if the current flowing through the switch is larger than the current threshold. The off time of the switch is determined by the load. The current threshold is variable at light load to prevent generating the audible noise and improve the whole efficiency.08-12-2010
20100201334SYNCHRONOUS RECTIFIER HAVING PHASE LOCK CIRCUIT COUPLED TO FEEDBACK LOOP FOR RESONANT POWER CONVERTERS - A synchronous rectifier for a switching power converter is provided and includes a power transistor, a diode, and a control circuit. The power transistor and the diode are coupled to a transformer and an output of the power converter for the rectification. The control circuit generates a drive signal to switch on the power transistor once the diode is forward biased. The control circuit includes a phase-lock circuit. The phase-lock circuit generates an off signal to switch off the power transistor in response to a pulse width of the drive signal. The pulse width of the drive signal is shorter than a turned-on period of the diode. The phase-lock circuit further reduces the pulse width of the drive signal in response to a feedback signal. The feedback signal is correlated to an output load of the power converter.08-12-2010
20080278134SWITCHING POWER SUPPLY DEVICE - The present invention provides a switching power supply device including a switching element, a control circuit controlling the switching element, a transformer having an auxiliary winding, a potential clamp circuit connected to one of outputs of the transformer, a delay capacitor connected to an output of the potential clamp circuit, a potential detection circuit detecting a potential at the delay capacitor, and an overload protection actuation circuit realizing overload protection. During an overload, the delay capacitor is charged only by ringing of the auxiliary winding, generated immediately after the switching element is turned off, through the potential clamp circuit. Then, the potential detection circuit supplies an actuation signal to a latch stop circuit by detecting that the potential at the delay capacitor rises. The latch stop circuit latches and stops the switching operation of the switching element to realize the overload protection when the actuation signal is fed into the latch stop circuit. Thus, the overload protection can be realized with a sufficient delay time by the relatively small delay capacitor.11-13-2008
20120105040Switched Inductor DC-DC Converter - A direct current to direct current (DCDC) voltage converter is described comprising a controller and at least one converter circuit. The converter circuit comprises at least first and second inductors, each having an input and an output; a first input switch connected to the input of the first inductor; a second input switch connected to the input of the second inductor; and an output switch connected to the outputs of the inductors for selectively combining the outputs to form a parallel combination of the inductors or a series combination of the inductors. The controller generates signals for selectively connecting the first and second input switches and the output circuit between a pair of power supply input terminals and a pair of power supply output terminals. In response to appropriate signals from the controller, the converter circuit can be operated as a buck converter or a boost converter.05-03-2012
20090160415METHOD AND APPARATUS TO CONTROL A POWER SUPPLY FOR HIGH EFFICIENCY - A power supply control circuit is disclosed. In one aspect, a power supply control circuit includes a controller to be coupled to a switch to regulate an output of a power supply in response to a feedback signal and a parameter change signal. A parameter response circuit is coupled to generate the parameter change signal in response to a difference between a first value of a parameter measured before an event and a second value of the parameter measured after the event. The difference between the first value of the parameter and the second value of the parameter is representative of the relative efficiency of the power supply.06-25-2009
20090128115VOLTAGE REGULATOR AND CONTROLLING METHOD THEREOF - A controlling method of a voltage regulator is provided. The voltage regulator at least includes a differential circuit and a pump high-voltage circuit which has a bias path, an output transistor and an output terminal. The controlling method includes steps of: providing at least a pre-charge path to the pump high-voltage circuit, closing the bias path and charging the output terminal with the pre-charge path when the output terminal is transient, detecting an output level of the output terminal, and closing the pre-charge path and open the bias path to bias the output transistor when the output level reaches a predetermined value.05-21-2009
20120068680METHOD AND APPARATUS FOR IMPLEMENTING SLEW RATE CONTROL USING BYPASS CAPACITOR - An example circuit includes a regulator circuit coupled to first and second nodes. A capacitance circuit and a slew rate control circuit are coupled between the first and second nodes. The regulator circuit is coupled to charge a capacitance of the capacitance circuit with a charge current. The slew rate control circuit is coupled to control a change in voltage over change in time between the first and second nodes during a power up mode of the circuit. The slew rate control circuit further includes a switch and a resistor. The slew rate control circuit is coupled to switch the switch in response to a voltage between the first and second nodes. A voltage drop across the resistor is limited to a base-emitter voltage drop of a transistor coupled between the first and second nodes to set the change in voltage over change in time.03-22-2012
20080315851SEMICONDUCTOR DEVICE AND POWER SUPPLY USING THE SAME - A power-supply control IC is included in a switching power supply which drives to turn on and off a semiconductor switching device connected to a DC power supply in series to supply a predetermined constant voltage to an external load, and is a semiconductor device including a semiconductor circuit which controls on and off of the semiconductor switching device. When a current flowing through the load is abruptly increased to cause an error voltage to exceed a predetermined first threshold voltage after the end of a PWM on-pulse generated in synchronization with a switching cycle, a second PWM on-pulse is generated within the same switching cycle. Furthermore, in a plurality of switching cycles after the switching cycle in which the second PWM on-pulse is generated, the first threshold voltage for comparison with the error voltage is switched to a second threshold voltage higher than the first threshold voltage.12-25-2008
20090085547Switching Power Supply Unit - A step-up switching power supply unit for generating a predetermined output voltage through a feedback control of its output voltage based on a first detection voltage indicative of the output voltage. The power supply unit is adapted to monitor a second detection voltage associated with the output voltage that is compared with a reference voltage. Open-circuit malfunction arising from, for example, connection failures within the power supply unit can be detected by determining whether the second detection voltage is lower than the reference voltage or not. In the event that open-circuit malfunction has taken place, the switching signal controlling the power supply unit is promptly stopped, thereby preventing abnormal rise of the output voltage (i.e. over-voltage).04-02-2009
20090212755METHOD AND APPARATUS TO PROVIDE TEMPORARY PEAK POWER FROM A SWITCHING REGULATOR - Various techniques directed to providing temporary peak power from a switching regulator are disclosed. In one aspect, a switching regulator includes a switch that is to be coupled between a power supply input and an energy transfer element of the power supply. A controller is coupled to be responsive to a feedback signal to be received from an output of the power supply. The controller is coupled to switch the switch in response to the feedback signal to regulate the output of the power supply. An oscillator is coupled to provide an oscillating signal to the controller to determine a maximum switching frequency of the switch. The oscillating signal is coupled to oscillate at a first frequency under a first moderate load condition at the power supply output. The oscillating signal is coupled to oscillate at a second frequency under a second peak load condition at the power supply output.08-27-2009
20090256543HIGH EFFICIENCY BRIDGELESS PFC POWER CONVERTER - A bridgeless PFC power converter comprises a first inductor and a second inductor coupled from a first input-terminal and a second input-terminal to a first transistor and a second transistor. A first diode and a second diode are coupled from the first transistor and the second transistor to an output capacitor. A first capacitor and a second capacitor are coupled from the input-terminals to the ground terminal through a third transistor and a fourth transistor. A control circuit generates a first-switching signal and a second-switching signal to control the first transistor and the second transistor. The second-switching signal will turn on the second transistor when the first-switching signal switches the first transistor. The first-switching signal will turn on the first transistor when the second-switching signal switches the second transistor. The control circuit turns off the third transistor and the fourth transistor during the light-load of the PFC power converter.10-15-2009
20090256542POWER SUPPLY CIRCUIT - A power supply circuit has a constant voltage circuit, a first MOS transistor, a second MOS transistor, a third MOS transistor, a first voltage dividing circuit that outputs a first divided voltage obtained by dividing the voltage of the output terminal by a first voltage dividing ratio, and a first differential amplifier circuit which is fed with a reference voltage and the first divided voltage and has an output connected to a gate of the second MOS transistor. The first differential amplifier circuit outputs a signal to turn on the second MOS transistor when the first divided voltage is higher than the reference voltage, and the first differential amplifier circuit outputs a signal to turn off the second MOS transistor when the first divided voltage is lower than the reference voltage.10-15-2009
20120194159INTERLEAVING FUNCTION POWER SUPPLY CONTROLLER AND METHOD THEREFOR - At least one exemplary embodiment is directed to a method of switching between synchronous and nonsynchronous ramp control.08-02-2012
20100156378METHOD AND APPARATUS TO CONTROL A POWER SUPPLY FOR HIGH EFFICIENCY - A power supply control circuit is disclosed. In one aspect, a power supply control circuit includes a controller to be coupled to a switch to regulate an output of a power supply in response to a feedback signal and a parameter change signal. A parameter response circuit is coupled to generate the parameter change signal in response to a difference between a first value of a parameter measured before an event and a second value of the parameter measured after the event. The difference between the first value of the parameter and the second value of the parameter is representative of the relative efficiency of the power supply.06-24-2010
20120194160VOLTAGE GENERATORS HAVING REDUCED OR ELIMINATED CROSS CURRENT - Embodiments described include voltage generators having reduced or eliminated cross current. Dynamic adjustment of a low or high threshold voltage used in a voltage generator is described. Use of a folded cascade amplifier in a voltage generator is also described.08-02-2012
20100219803DC TO DC CONVERTER AND METHOD FOR REDUCING OVERSHOOT - A DC to DC converter includes a control circuit, a gate driver circuit, and a power stage circuit. The control circuit receives and compares a DC output voltage. When the DC output voltage lower than a first threshold voltage, a PWM signal with a first frequency is outputted, and when the DC output voltage higher than the first threshold voltage, the PWM signal with a second frequency is outputted. The second frequency is higher than the first frequency. The gate driver circuit receives the PWM signal and converts the PWM signal to a first driving signal and a second driving signal. The power stage circuit converts a DC input voltage to the DC output voltage according to the first driving signal and the second driving signal.09-02-2010
20090273327POWER SUPPLY DEVICE, ELECTRONIC DEVICE USING THE SAME, AND SEMICONDUCTOR DEVICE - A linear regulator is provided which stabilizes an input voltage based on a reference voltage source that generates a reference voltage, and the reference voltage generated by the reference voltage. An output voltage of the linear regulator is supplied as a power supply voltage of a switching controller and the reference voltage source. The linear regulator is configured to enable switching of a regulation mode in which voltage is outputted according to the reference voltage, and a bypass mode in which an input voltage is outputted as it is, with no relation to the reference voltage. When a power supply apparatus is started up, during a time period until the input voltage reaches a predetermined threshold voltage, the linear regulator operates in the bypass mode, and when the input voltage exceeds the threshold voltage, operates in the regulation mode.11-05-2009
20090284239Quick response mechanism and method for a switching power system - A quick response mechanism for a switching power system includes a detector and an adjustor connected to the detector. The detector is configured to directly monitor the drop of the output voltage of the switching power system so that a quick response could be immediately triggered when a load transient occurs. The adjustor is configured to adjust the duration of the quick response, thereby preventing the output voltage from undershoot or ringback.11-19-2009
20090322301Control circuit for improving efficiency of lower load of power supply device and method thereof - In a control circuit and a method for improving the efficiency of a lower load of a power supply device, the power supply device includes power stages, for inputting an input power to the power supply device and producing an output power to drive a load; a control circuit electrically coupled to the power stages for detecting a drive load and issuing a control signal for turning on/off one of the power stages. The control method includes: setting a predetermined output load value by a control circuit; detecting a total output load of the power stages by the control circuit; comparing the total output load with the predetermined output load value; and turning on/off one of the power stages by the control circuit according to a comparison result. The invention reduces the loss of power stages at a low load to enhance the power saving effect and the economic efficiency.12-31-2009
20100219802QUASI-RESONANT SYSTEMS AND METHODS WITH MULTI-MODE CONTROL - Switch-mode power conversion system and method thereof. The switch-mode power conversion system includes a primary winding configured to receive an input voltage, and a secondary winding coupled to the primary winding and configured to, with one or more other components, generate an output signal. Additionally, the switch-mode power conversion system includes a feedback component configured to receive the output signal and generate a feedback signal based on at least information associated with the output signal, and a voltage detector configured to receive the input voltage and output a detection signal. Moreover, the switch-mode power conversion system includes a mode controller configured to receive the detection signal and the feedback signal and generate a switch signal based on at least information associated with the detection signal and the feedback signal, and a switch configured to receive the switch signal and affect a first current flowing through the primary winding.09-02-2010
20090322300HYSTERETIC BUCK CONVERTER HAVING DYNAMIC THRESHOLDS - A hysteretic buck converter provides improved regulation control, in particular for buck converter standby operation. A comparison circuit compares the output voltage of the buck converter to a waveform that is generated from an indication of the output current of the converter, so that the turn-on time of the converter is advanced as the output current demand increases. The resulting action anticipates a reduction in output voltage due to the increased current, preventing an excursion of the output voltage below the ripple voltage minimum. The turn-off time of the converter is controlled by an upper threshold that limits the ripple voltage maximum. The output current indication may be a measurement of output current, or may be a dynamic value calculated from the input voltage and the output voltage waveform.12-31-2009
20090039853POWER SUPPLY DEVICE AND ELECTRONIC APPLIANCE PROVIDED THEREWITH - A power supply device has an error amplifier producing an error voltage by amplifying a difference between a feedback voltage according to an output voltage and a predetermined reference voltage, an output portion producing a desired output voltage from an input voltage in such a way that the error voltage is reduced, and a clamping portion setting, during a predetermined period after startup of the power supply device, an upper limit of the error voltage to a value that is lower than a value obtained at normal times, such that the lower the input voltage the higher the upper limit, the higher the input voltage the lower the upper limit.02-12-2009
20090167272Power Supply Controller - A first current corresponding to the drain-to-source voltage of a power MOSFET can pass through an FET; and a second current corresponding to a constant voltage can pass through an FET; a third current corresponding to the difference determined by subtracting the first current from the second current can pass into threshold setting resistors from the connecting point between FETs. Consequently, divided voltages at the connecting points between the threshold setting resistors varies directly with a voltage corresponding to the difference determined by subtracting the drain-to-source voltage of the power MOSFET from the constant voltage.07-02-2009
20110127984LINEAR VOLTAGE REGULATOR CIRCUIT WITH POWER SAVING CAPABILITY - A linear voltage regulator circuit includes first and second voltage input terminals to receive a first or second external voltage, a voltage output terminal, a voltage regulator unit, a voltage switch unit, and a voltage detecting unit. The voltage regulator unit selectively receives the first or second external voltage controlled by the voltage switch unit. The voltage detecting unit outputs a first control signal to control the voltage switch unit to output the first external voltage to the voltage regulator unit, in response to an output voltage of the voltage output terminal being less than or equal to a predetermined value. The voltage detecting unit outputs a second control signal to control the voltage switch unit to output the second external voltage to the voltage regulator unit in response to the output voltage being greater than the predetermined value.06-02-2011
20110241641Current Mode Buck Converter with Fixed PWM/PFM Boundary - A current mode buck converter is disclosed. The buck converter operates in a pulse width modulation (PWM) mode or a pulse frequency modulation (PFM) mode. To prevent an output inductor with various probable magnitudes from varying a decision boundary between the PWM mode and the PFM mode, the buck converter adaptively adjusts a triggering condition for the pulse frequency modulation mode according to an average value of an inductor current of the output inductor or AC components of the inductor current and a slope compensation current.10-06-2011
20110109292METHODS AND SYSTEMS FOR CONTROLLING BOOST CONVERTERS - A method for controlling a boost converter having a duty cycle includes the steps of receiving an electric current command for the boost converter, measuring a source current for the boost converter, regulating the duty cycle as a function of the electric current command and the source current, subject to a first minimum limit if a rapid change in duty cycle is required above a predetermined threshold and a second minimum limit if the rapid change in duty cycle is not required.05-12-2011
20090140710METHOD AND APPARATUS FOR A HIGH VOLTAGE POWER SUPPLY CIRCUIT - A high voltage power supply method and apparatus is disclosed. An example power supply circuit includes a rectifier circuit coupled to receive an AC input voltage. A switchmode power converter circuit is coupled to the rectifier circuit to receive a rectified input voltage to generate a regulated output voltage. A switch is coupled between the rectifier circuit and the switchmode power converter circuit. A sense circuit is coupled to detect the AC input voltage. The sense circuit is coupled to turn off the switch when an absolute value of the AC input voltage exceeds a first threshold value. The sense circuit is coupled to turn on the switch when the absolute value of the AC input voltage is below a second threshold value.06-04-2009
20090066308Switched Mode Power Supply Having Variable Minimum Switching Frequency - In a switched mode power supply (SMPS) that regulates an output voltage in response to load conditions by switching an inductor circuit between a supply voltage and ground at a switching frequency, under light loading conditions, the switching frequency of the SMPS is reduced down to a variable minimum switching frequency sufficiently high to avoid audible noise generation.03-12-2009
20100176783SWITCHING DEVICE DRIVE CIRCUIT - A gate voltage detecting circuit 07-15-2010
20110115458DIGITAL SLOPE COMPENSATION FOR CURRENT MODE CONTROL - A digital slope compensation apparatus and method for a switched-mode power supply use a sensor for sensing and generating an analog inductor current (i05-19-2011
20110115457METHOD OF CONTROLLING OF A SWITCHED-MODE POWER SUPPLY AND CORRESPONDING POWER SUPPLY - A method of controlling a switched-mode power supply and corresponding power supply including a switching cell including two series-connected configurable on/off switches; in which the switching cell is configured cyclically: for a duration T1, in an on state, in which a first on/off switch is closed and the second on/off switch is open; and, for a duration T2, in an off state, in which the second on/off switch is closed and the first on/off switch is open. The switching cell is also configured in a transition state, in which the first on/off switch and the second on/off switch are open: for a duration Tm1 between the off state and the on state; and for a duration Tm2 between the on state and the off state; and the durations T1 and/or T2 of the on and off states are determined according to the durations Tm1 and/or Tm2, respectively, of the transition states.05-19-2011
20110084678MULTI-THRESHOLD MULTI-GAIN ACTIVE TRANSIENT RESPONSE CIRCUIT AND METHOD FOR DIGITAL MULTIPHASE PULSE WIDTH MODULATED REGULATORS - Disclosed is a multi-phase pulse width, modulated voltage regulator and method in which transient voltage excursions or deviations that exceed the load line voltage by more than a pre-determined amount are detected by an ATR circuit and a correction signal is applied. The correction signal is in the form of asynchronous pulses and the number of such pulses is a function of the magnitude of the voltage excursion as determined by the number of thresholds that are exceeded. Also disclosed is an adaptive voltage positioning (AVP) circuit and method for early detection of a transient event by sensing voltage changes at the load and adjusting the target voltage with pre-determined current values prior to the time that ATR event changes in the current at the load are detected.04-14-2011
20090033304Low-Loss Control of DC-DC Converters In An Energy Storage System - An energy storage system including a buck-boost DC-DC converter operable so as to minimize switching loses. The system includes a first energy storage device, e.g., a bank of ultracapacitors, and a second energy storage device, e.g., a second bank of electrolytic capacitors. Both first and second energy storage devices are connected to the DC-DC converter. The DC-DC converter is operated in a non-standard manner so as to reduce switching and other losses. In particular, the DC-DC converter may be operated in an alternate buck mode so as to force on a switch S02-05-2009
20110080150Systems and Methods for DC to DC Conversion with Current Mode Control - In one embodiment the present invention includes a DC to DC converter device which includes an electronic circuit. The electronic circuit comprises a first comparator, a second comparator, a first switch, a first latch, and a current sensor. The inductor current includes a peak current value and a valley current value. The first comparator detects the peak current value and resets the first latch which opens the first switch. The second comparator detects the valley current value and sets the first latch which closes the first switch. The current sensor is coupled to sense an inductor current flowing through an output load, and is coupled to provide a sense voltage to the first and second comparators. In this manner, the electronic circuit provides DC to DC conversion with current control.04-07-2011
20110084677POWER SUPPLIES AND ASSOCIATED METHODS OF CONTROL - Switching mode power supplies (SMPS) that can operate in a control mode for a normal load condition and operate with a burst-mode controller for a light load condition are disclosed herein. In one embodiment, a method for controlling the switching mode power supply includes when the load is in a light load condition, the switching mode power supply is controlled by a burst-mode controller.04-14-2011
20090322303SWITCHING REGULATOR - In a switching regulator, when a control switching signal received from outside is indicating PWM control, a second reference voltage generating circuit outputs, as a second reference voltage, a voltage that is lower than the minimum voltage of an output voltage range of an error amplifying circuit, so that output signals from a comparator are fixed at a high level. When a control switching signal received from outside is indicating VFM control, the second reference voltage generating circuit adjusts the second reference voltage according to the voltage difference between an input voltage and an output voltage, because the optimum second reference voltage varies according to the voltage difference between the input voltage and the output voltage.12-31-2009
20090322302Power Supply Circuit and Electronic Equipment - A power supply circuit comprising: a voltage generating circuit configured to generate an output voltage of a target level from an input voltage; an overcurrent protection circuit configured to control the voltage generating circuit so as to stop an output current, when a level of the output current generated at a time of generating the output voltage is greater than a reference level; and a reference-level change circuit configured to change the reference level in the overcurrent protection circuit to be at a second level higher than a first level from the first level for a predetermined period, when the overcurrent protection circuit detects that the level of the output current is greater than the reference level.12-31-2009
20100066336POWER CONTROL CIRCUIT - A control circuit 03-18-2010
20100231190DC/DC VOLTAGE REGULATOR WITH AUTOMATIC CURRENT SENSING SELECTABILITY FOR LINEAR AND SWITCH MODE OPERATION UTILIZING A SINGLE VOLTAGE REFERENCE - A switch-mode DC/DC converter and a linear low drop out (LDO) DC/DC regulator are connected in parallel to drive a single load. Both regulators share a common voltage reference, feedback network, input supply and output such that the regulated voltage is identical during each mode of operation. During heavy loads the switch-mode regulator is in operation and the linear regulator is disabled for the highest efficiency possible. Conversely at light loads the linear regulator is in operation with the switch-mode regulator disabled, also maximizing the efficiency. Each regulator senses load current to automatically transition between the appropriate voltage regulators at fixed load current levels. The presented invention also includes a make before break transition scheme of the voltage regulators to minimize the voltage transients.09-16-2010
20100244802Power Converter with Transient Processing Capability - Transient processing mechanisms for power converters. Error generation circuitry in a power converter may generate an error signal based on the difference between a power converter output voltage and a reference voltage. Transient detection circuitry may detect whether the error signal exceeds at least a first threshold. If the first threshold is exceeded, timing control logic may generate a low band correction pulse to adjust the power converter output voltage, and thereby adjust the error signal to a level within the first threshold. If the error signal exceeds a second threshold, the timing control logic may generate a high band correction pulse to adjust the power converter output voltage, and thereby adjust the error signal to a level within the second threshold. The timing control logic may initiate a low band blanking period following the low band correction pulse and high band blanking period following the high band correction pulse.09-30-2010
20100244801CONTROLLER FOR SWITCHING REGULATOR, SWITCHING REGULATOR AND LIGHT SOURCE - A switching regulator (09-30-2010
20100244800SWITCHING POWER SUPPLY UNIT AND CONTROL CIRCUIT FOR SAME - There is provided a switching power supply unit having an overcurrent detection circuit capable of automatically selecting either a current detection method using an resistor or a current detection method using an external current detection resistor and of performing optimized overcurrent protection depending on applications. In the control circuit of the switching power supply unit for detecting a current flowing through a high-side switch as a current detection signal and comparing it with an overcurrent detection threshold value to detect an overcurrent and turning off the high-side switch to protect the switching power supply unit, a first current detection terminal connected to a power supply side terminal of the high-side switch or to a load side terminal of the high-side switch and a temperature compensating means to switch for temperature compensation on an overcurrent detection threshold value or on a current detection signal are provided.09-30-2010
20100301825DC-DC CONVERTER - A DC-DC converter has an error amplifier that amplifies a potential difference between a first voltage based on an output voltage at the output terminal and a reference voltage, and outputs a resultant error amplified signal; a differential detecting circuit that senses an inclination of a temporal change of the output voltage by differentiating the first voltage, outputs a control signal according to a result of the sensing; and a PWM generating circuit that compares a synthetic signal obtained by conducting computation on the amplified error signal and the control signal with a periodically changing comparison signal, and outputs a PWM signal having a duty ratio controlled according to a result of the comparison.12-02-2010
20110254527ANALOG CURRENT OUTPUT CIRCUIT - In the analog current output circuit according to the present invention, a rising start position and a tilt of an internal control voltage are set such that it crosses, at the maximum of an analog output current, a load end voltage obtained when the resistance of a load is the one near the center of a specification range. According to a comparison result in a comparator, a switch causes a DC/DC converter to input a high reference voltage and causes an output transistor to output a high power supply voltage when the internal control voltage is smaller than the load end voltage and causes the DC/DC converter to input a low reference voltage and causes the output transistor to output a low power supply voltage when the internal control voltage is larger than the load end voltage.10-20-2011
20100085027SYSTEM AND METHOD FOR PROVIDING LINEAR BUCK BOOST TRANSITIONS WITHIN A BUCK BOOST CONVERTER - A voltage regulator, comprising first circuitry for generating an output voltage responsive to an input voltage and a plurality of switching control signal. Switching control circuitry generates the switching control signals responsive to the output voltage and at least one of a buck ramp signal and a boost ramp signal. Voltage ramp generation circuitry generates each of the buck ramp signal and the boost ramp signal. The boost ramp signal comprises the buck ramp signal offset by the peak value of the buck ramp signal.04-08-2010
20110254526Voltage Regulator with Optimal Efficiency Selection and a Master-Slave Zero Cross Detection Configuration - A voltage regulator includes a first phase power stage, a second phase power stage, and a controller. The first phase power stage includes a zero cross detection circuit configured to measure a current level for the first phase power stage, and to cause a diode emulation state in the first phase power stage when the current level is substantially equal to zero. The second phase power stage is in communication with the zero cross detection circuit, and configured to enter the diode emulation state in response to receiving a signal from the zero cross detection circuit. The controller is coupled to the first phase power stage and to the second phase power stage. The controller is configured to measure an output current of the voltage regulator and to activate the second phase power stage when the output current is above a first threshold current level.10-20-2011
20120200277INSTANTANEOUS AVERAGE CURRENT MEASUREMENT METHOD - Circuitry and method for providing a signal indicative of instances of conduction of average inductor current in a DC-to-DC voltage converter. Such signal identifies a time when the instantaneous average current being conducted by the inductor in a DC-to-DC voltage converter can be measured by providing a signal edge approximately halfway through one of the increasing and decreasing current conduction intervals of the inductor.08-09-2012
20100320988INTERNAL VOLTAGE SUPPLYING DEVICE - An internal voltage supplying device. A reference voltage generator generates a first feedback voltage having a predetermined voltage ratio with respect to a core voltage. An adjusting mechanism adjusts the voltage ratio, and a voltage generator supplies a high voltage having a level higher than a level of the core voltage by the level of a threshold voltage or higher and maintains the level of the high voltage in accordance with the first feedback voltage.12-23-2010
20100320987QUASI-CONTINUOUS VOLTAGE REGULATOR AND CONTROLLER - A controller for a voltage regulator includes a hysteretic circuit that generates a hysteretic voltage output as a function of a regulated voltage and that generates a hysteretic current output as a function of an inductor current. A switch control circuit provides a quasi-continuous control output as a function of the hysteretic current output from a start time when the regulated voltage rises above a higher hysteretic voltage until a stop time when the regulated voltage falls below a lower hysteretic voltage.12-23-2010
20100320986SWITCHING CONVERTERS WITH EFFICIENTLY-CONTROLLED MODE TRANSITIONS - Efficiently controlled converter system embodiments are provided to operate in different operational modes. In a first operational PWM mode, first and second transistors are switched with a feedback-controlled duty cycle to thereby realize an inductor current that maintains a system output voltage. In a second operational PFM mode, after the output voltage decays to a lower threshold over a decay time, the control and synchronous transistors are driven a sufficient number of times to raise the output voltage to an upper threshold. The systems are controlled to efficiently transition between the first and second operational modes. For example, a converter system preferably transitions to the second PFM operational mode when current peaks of the inductor current drop below a predetermined current threshold and the system preferably transitions to the first PWM operational mode when the output voltage drops to a predetermined reference voltage.12-23-2010
20100283443Circuit Arrangement for Supplying An Output Current to a Load - A circuit arrangement for supplying an output current to a load which is useable in power supplies and is connectable in parallel to other circuit arrangements, wherein effects of component tolerances on a uniform working load are avoided.11-11-2010
20120146608VOLTAGE REGULATOR AND PULSE WIDTH MODULATION SIGNAL GENERATION METHOD THEREOF - In a PWM signal generation method of a voltage regulator, an output sense signal, a first ramp signal and a second ramp signal are provided. A first time point of the first ramp signal crossing with the output sense signal is used to determine a start point of an ON-time of a PWM signal, and a second time point of the second ramp signal crossing with the output sense signal is used to determine an end point of the ON-time of the PWM signal. Moreover, the first ramp signal is reset to a reference voltage at the first time point and then maintained at the reference voltage, and further ramps down starting from the end point of the ON-time. The second ramp signal ramps up starting from the start point of the ON-time, and then is reset to a preset voltage at the second time point.06-14-2012
20100213912Quick Response Power Supply Switching Device and Power Supply Network Including Such a Switch - The present invention relates to a quick response power supply switching device. It also relates to a power supply network equipped with such a switch. The electrical power supply is connected to a set of blocks, the device comprises at least one switch (08-26-2010
20100213913VOLTAGE REGULATOR - Provided is a voltage regulator that is capable of improving a transient response characteristic while suppressing current consumption. A fluctuating output voltage is detected without increasing the current consumption of a differential amplifier, and a phase compensation resistor (08-26-2010
20080218143METHOD AND APPARATUS TO PROVIDE TEMPORARY PEAK POWER FROM A SWITCHING REGULATOR - Various techniques directed to providing temporary peak power from a switching regulator are disclosed. In one aspect, a switching regulator includes a switch that is to be coupled between a power supply input and an energy transfer element of the power supply. A controller is coupled to be responsive to a feedback signal to be received from an output of the power supply. The controller is coupled to switch the switch in response to the feedback signal to regulate the output of the power supply. An oscillator is coupled to provide an oscillating signal to the controller to determine a maximum switching frequency of the switch. The oscillating signal is coupled to oscillate at a first frequency under a first moderate load condition at the power supply output. The oscillating signal is coupled to oscillate at a second frequency under a second peak load condition at the power supply output.09-11-2008
20100194369DC-DC CONVERTER AND SWITCHING CONTROL CIRCUIT - A switching control circuit for controlling on/off of a switching element for driving an inductor for voltage conversion, the switching control circuit including: a voltage comparator for determining whether an output voltage of the inductor is in a first state where the output voltage is equal to or higher than a predetermined electric potential or in a second state where the output voltage is lower than the predetermined electric potential; a timing determination unit for determining an on-timing to turn on the switching element based on a clock signal having a predetermined frequency even when the output voltage is in the first state; and a drive control circuit for generating a driving signal to turn on or turn off the switching element based on an output signal of the timing determination unit.08-05-2010
20100194367METHOD AND APPARATUS TO REGULATE AN OUTPUT VOLTAGE OF A POWER CONVERTER AT LIGHT/NO LOAD CONDITIONS - An example apparatus to regulate an output voltage of a power converter at light/no load conditions includes a driver circuit, a feedback circuit, and an adjustable voltage reference circuit. The driver circuit is coupled to output a drive signal to switch a power switch between an ON state and an OFF state to regulate an output of the power converter. The feedback circuit is coupled to the driver circuit and is further coupled to output an enable signal to switch the power switch to an ON state in response to an output voltage signal. The adjustable voltage reference circuit is coupled to adjust a voltage reference such that a bias winding voltage of the power converter is adjusted nonlinearly in response to a load that is to be coupled to the output of the power converter.08-05-2010
20110148379CLEAN TRANSITION BETWEEN CCM AND DCM IN VALLEY CURRENT MODE CONTROL OF DC-TO-DC CONVERTER - A valley current mode DC-to-DC converter may include an electronic control system configured to cause the DC-to-DC converter to operate under a continuous current mode and a discontinuous current mode. The electronic control system may include a current sensing system configured to sense current traveling through an inductance, a dual threshold generator configured to generate a first and a different second threshold, and a comparator system configured to compare current sensed by the current sensing system with the first threshold when the DC-to-DC converter is operating in the continuous current mode and with the second threshold when the DC-to-DC converter is operating in the discontinuous current mode.06-23-2011
20110148380CIRCUIT AND METHOD FOR ADJUSTING AN OFFSET OUTPUT CURRENT FOR AN INPUT CURRENT AMPLIFIER - A circuit and a method for correcting an offset is provided that includes a current amplifier and an adjusting circuit for correcting an offset of an output current of the current amplifier. Wherein the adjusting circuit has a controlled current source, an output of the controlled current source is connected to the current amplifier for impressing an output current of the controlled current source in the current amplifier, an input of the controlled current source to form a regulation element of a control loop is connected by a first switching device of the adjusting circuit to an output of the current amplifier and to form a holding element is disconnected from the output of the current amplifier by the first switching device. The controlled current source, acting as a regulation element in the control loop, is set up to regulate the offset to a minimum by setting of a current value of the output current, and the controlled current source, acting as a holding element, is set up to hold the current value, associated with the minimum, of the output current.06-23-2011
20100026265POWER SUPPLY UNIT HAVING CONFIGURABLE OUTPUT VOLTAGE RANGES - As a result of a path being connected to an input terminal to allow a first intermediate voltage from a power-side regulator or another external source that does not pass through the power-side regulator to be selectively inputted into any supply-side regulator, a supply voltage can be generated based on the inputted voltage. Therefore, as a result of the relevant supply-side regulator being connected to a path by which the other external source is inputted, a supply voltage having a voltage value differing from that when the first intermediate voltage is inputted can be generated. As a result of the voltage inputted into the supply-side regulator being changed, only the voltage value of the supply voltage generated by the supply-side regulator is changed. Therefore, the variation of the voltage value of the supply voltage that can be provided by a power supply unit can be changed.02-04-2010
20100019750POWER CONVERTOR AND CURRENT DETECTION APPARATUS THEREOF - A current detection apparatus including a current detection circuit, a voltage regulation power supply circuit, and a package carrier is disclosed. The current detection circuit has a reference terminal and a detection terminal. The voltage regulation power supply circuit is used to generate an output voltage and includes a current transmission terminal for transmitting a current. The package carrier is used to carry the current detection circuit, the voltage regulation power supply circuit, a reference pad, and a current transmission pad. The package carrier includes at least one common voltage lead. The current transmission pad is coupled to the reference pad through at least one bonding wire such that an equivalent resistance is formed on the coupling path between the current transmission pad and the reference pad.01-28-2010
20120146609SWITCHING CONTROL CIRCUIT - A switching-control circuit configured to keep a transistor on for a predetermined time to generate a target-level-output-voltage from an input voltage. The circuit configured to generate, every switching period of the transistor, a slope voltage corresponding to that of a ripple voltage contained in an output voltage during a time period when the transistor is off, limit an amplitude of the slope voltage so as not to exceed a predetermined amplitude greater than the amplitude of the slope voltage when the target-level-output-voltage is generated, add the slope voltage to a reference voltage, indicating a reference of the target-level-output-voltage, or a feedback voltage corresponding to the output voltage, and keep the transistor on for a predetermined time and thereafter turn off the transistor, when a level of either one voltage, added with the slope voltage, of the reference voltage and the feedback voltage reaches a level of another voltage thereof.06-14-2012
20110109293SYSTEMS AND METHODS FOR LIMITING INPUT POWER AND RMS INPUT CURRENT DRAWN FROM A DC POWER SOURCE - Systems and methods to source a resistive load, such as a heating resistor, to control temperature while adhering to a specified power draw budget and/or a specified root mean square (RMS) current limit. For example, a sensor block assembly (SBA) heater controls temperature of a MEMS device in a sensor block assembly while adhering to the power draw budget and/or an average current limit. An exemplary embodiment generates a pulse width modulation (PWM) control signal, controls a switch in accordance with the control signal, sources the resistive load from a power source in accordance with the controlled switch, and modifies the duty factor of the switch to reduce the power drawn by the resistive load in response to the power drawn by the resistive load exceeding a power limit defined by a slope-intercept curve. The limiting of power into a resistor load limits the RMS current drawn by that load.05-12-2011
20120038341SWITCHING REGULATOR AND OPERATION CONTROL METHOD THEREOF - A non-isolated type switching regulator having an inductor includes: a switch element; a rectification element; an error amplifying circuit section amplifying a voltage difference between a feedback voltage and a first reference voltage and outputting as an error voltage; a first voltage comparison circuit section performing a voltage comparison of a ramp voltage which performs a voltage change set beforehand with the error voltage to be synchronized with the switching of the switch element and producing and outputting a first comparison signal; a second voltage comparison circuit performing a voltage comparison of the error voltage with a second reference voltage and producing and outputting a second comparison signal; an oscillation circuit section starting an oscillation based on the second comparison signal and producing and outputting a clock signal; and a control circuit section performing a switching control of the switch element based on the clock signal and the first comparison signal.02-16-2012
20120038340DYNAMIC CONTROL LOOP FOR SWITCHING REGULATORS - Some embodiments regard a method of controlling a regulator having an input voltage and an output voltage, comprising: turning on a first driver; determining a duration ratio having a first time period over the first time period and a second time period; the first time period and the second time period indicating a duration when the first driver and a second driver is on, respectively; generating a second voltage level for the reference voltage based on the duration ratio and a ripple voltage that is a difference between a high threshold voltage and a low threshold voltage; turning off the first driver and turning on the second driver based on a relationship between the second voltage level and a voltage level of the output voltage; turning off the second driver when a current flowing through a node of the output voltage reaches a pre-determined level; and generating a change in the first time period based on the duration ratio and a voltage difference between a peak of the output voltage and the high threshold voltage.02-16-2012
20100231189HIGH EFFICIENCY BUCK-BOOST POWER CONVERTER - A buck-boost power converter switches the switches thereof with a novel sequence and extends the switching periods of the switches to reduce the switching loss and conduction loss when the input voltage thereof approaches the output voltage thereof. The influence of the load current of the power converter on the duty thereof is taken into account to switch the power converter between modes at correct time points, so as to prevent the output voltage from being affected by the mode switching.09-16-2010
20090201003DC/DC CONVERTER - A conventional DC/DC converter with both a step-up function and a step-down function has a drawback that its output voltage will be discontinuous when its operations are switched.08-13-2009
20110050192METHODS FOR LIGHT LOAD EFFICIENCY IMPROVEMENT OF A BUCK BOOST VOLTAGE REGULATOR - Methods are proposed for a buck boost voltage regulator to monitor the output voltage or both the inductor current and the output voltage of the buck boost voltage regulator to control the buck boost voltage regulator to reduce the switching times of the power switches of the buck boost voltage regulator to improve the light load efficiency of the buck boost voltage regulator.03-03-2011
20080203990SWITCHING REGULATOR - A switching regulator that includes an inductor, a first step-down switch to store charge in the inductor, a second step-down switch to discharge the charge, a first step-up switch to store charge in the inductor, a second step-up switch to discharge the charge, a reverse current detector to detect a reverse current from an output terminal to the inductor through the second step-up switch, or an indication of the reverse current, based on a detection voltage, and a controller to control the first and second step-down switches, and the first and second step-up switches to output a predetermined constant voltage, and to shut off the second step-up switch to make shutdown condition when the detector detects the reverse current or an indication of the reverse current. The reverse current detector may have a threshold value in the step-down operation that is different from a threshold value in the step-up operation.08-28-2008
20120043954QUASI-RESONANT SYSTEMS AND METHODS WITH MULTI-MODE CONTROL - Switch-mode power conversion system and method thereof. The switch-mode power conversion system includes a primary winding configured to receive an input voltage, and a secondary winding coupled to the primary winding and configured to, with one or more other components, generate an output signal. Additionally, the switch-mode power conversion system includes a feedback component configured to receive the output signal and generate a feedback signal based on at least information associated with the output signal, and a voltage detector configured to receive the input voltage and output a detection signal. Moreover, the switch-mode power conversion system includes a mode controller configured to receive the detection signal and the feedback signal and generate a switch signal based on at least information associated with the detection signal and the feedback signal, and a switch configured to receive the switch signal and affect a first current flowing through the primary winding.02-23-2012
20110156687EFFICIENCY MEASURING CIRCUIT FOR DC-DC CONVERTER WHICH CALCULATES INTERNAL RESISTANCE OF SWITCHING INDUCTOR BASED ON DUTY CYCLE - An efficiency measuring circuit may measure the efficiency of a DC-DC converter having a switching inductor with an internal DC resistance and a plurality of electronic switches that control current through the inductor. A duty cycle circuit may measure the duty cycle of current flowing through one of the electronic switches. A current sense circuit may measure the current flowing through one of the electronic switches. An inductor voltage sensor circuit may measure the voltage across the inductor. A computation circuit may compute the internal DC resistance of the switching inductor based in part on the duty cycle measured by the duty cycle circuit and the current measured by the current sense circuit. The computation circuit may also compute the efficiency of the DC-DC converter.06-30-2011
20110156685CONSTANT TIME BUCK-BOOST SWITCHING REGULATOR AND CONTROL CIRCUIT AND METHOD FOR THE SAME - The present invention discloses a constant time buck-boost switching regulator, and a control circuit and a method for controlling the buck-boost switching regulator. The buck-boost switching regulator includes an inductor, a first and a second power switches coupled to a first end and a second end of the inductor respectively, and a first and a second power devices coupled to the first end and the second end of the inductor respectively, the first power switch being coupled between the first end of the inductor and an input voltage, the second power switch being coupled between the second end of the inductor and ground, the first power device being coupled between the first end of the inductor and ground, and the second power device being coupled between the second end of the inductor and an output voltage. The control method comprises: generating only one single constant time; and generating a switch control signal to control the first and second power switches such that the first and second power switches operate by the same switching period with the same ON-time.06-30-2011
20110156686LDO REGULATOR WITH LOW QUIESCENT CURRENT AT LIGHT LOAD - A low dropout (LDO) regulator includes an amplifier having an input terminal, an output terminal; a first bias source and a second bias source, the first and second bias sources receiving a supply voltage, and a pass transistor and a sense transistor. Sources of the pass transistor and sense transistor are coupled to each other that receive the supply voltage. Gates of the pass transistor and sense transistor coupled to each other and to the output terminal of the amplifier. The LDO further includes a detection circuit responsive to a load current to deactivate the second bias source such that quiescent current in the amplifier is reduced. The detection circuit comprises a comparator coupled across a resistor. The resistor is coupled to a drain of the sense transistor.06-30-2011
20110156684DC-DC CONVERTERS WITH PULSE GENERATORS SHARED BETWEEN PWM AND PFM MODES - A DC-DC converter system having at least one DC-DC converter operating in either a PWM mode or a PFM mode is provided. The DC-DC converter system includes a state machine configured to control the switching between the PWM mode and PFM mode. The state machine determines whether an inductor current provided by the DC-DC converter reaches a first specified value for a selective number of clock cycles so switching between the PWM mode and PFM mode is to occur. A pulse generator circuit is connected to the state machine and being configured to provide the appropriate switching period for the PWM mode and the PFM mode at the time of switching. The pulse generator circuit is shared amongst the PWM mode or PFM mode and utilizes a master clock for its operations.06-30-2011
20110156688Regulator Over-Voltage Protection Circuit with Reduced Standby Current - An embodiment of the invention relates to a power converter formed with an error amplifier and a related method. In an embodiment, a first switch is coupled in series with an error amplifier compensation capacitor. Upon detection of a current level greater than a threshold level, the compensation capacitor is decoupled from the error amplifier by opening the first switch. In an embodiment, a second switch is coupled in parallel with the compensation capacitor, and the current-sensing circuit enables conductivity of the second switch to discharge the compensation capacitor upon detection of the current level greater than the threshold level. The second switch is opened upon detection of the current level less than the threshold level. In an embodiment, the current-sensing circuit controls an output current of the power converter at a current-limit level upon detection of the internal current level greater than the threshold level.06-30-2011
20120001610BUCK-BOOST REGULATOR WITH DEAD BAND - This document provides methods and apparatus configured to efficiently regulate an output voltage near a desired voltage level, for example, under varying input or load conditions. An example apparatus can include a regulator having a boost controller configured to provide voltage to an output of the regulator when at least one of the output voltage or the input voltage is below a first threshold voltage and a buck controller configured to provide voltage to the output of the regulator when at least one of the output voltage or the input voltage is above a second threshold voltage. Further, the regulator can be configured to provide the input voltage at the output of the regulator when at least one of the input voltage or the output voltage is between the first and second threshold voltages. In some examples, the first threshold is below the second threshold.01-05-2012
20090027026WINDOW COMPARATOR WITH ACCURATE LEVELS FOR USE IN DC-DC CONVERTERS - The present invention relates to a improved feedback circuit for generating a quantized control signal representing the relation of a signal to be controlled relative to predetermined limits of at least one error signal window, the circuit comprising signal detecting means, a detected signal connected to error amplifying means for amplifying the error between the detected signal and a first reference signal, the output error signal of the error amplifying means connected to at least a first comparator means and second comparator means each configured to compare the error signal with one of the upper limit and lower limit of the at least one error signal window. The invention provides a circuit and method by which only one accurate comparator is needed and for the error windows only simple, inaccurate comparators can be used. Thus, accuracy of the distance between the defined error window levels is much more fixed because it is primary determined by mismatch of resistors and not by the offset of the used comparators. Further, the capacitive load on the feedback node is smaller, which leads to a better response time. Furthermore, the current consumption is considerably less. Moreover, the circuit will be smaller. Finally, yet importantly, the overall offset of the output voltage is comparable to the offset in the standard solution.01-29-2009
20110025288METHOD AND APPARATUS FOR MAINTAINING A CONSTANT LOAD CURRENT WITH LINE VOLTAGE IN A SWITCH MODE POWER SUPPLY - A power supply regulator including a variable current limit threshold that increases during an on time of a switch. In one aspect, a power supply regulator includes a comparator coupled to receive a signal representative of a current through a switch during an on time of the switch. The comparator is further coupled to receive a variable current limit threshold that increases during the on time of the switch. The power supply regulator also includes a feedback circuit coupled to receive a feedback signal representative of an output of a power supply. A control circuit is also included and is coupled to the switch, to an output of the comparator, and to an output of the feedback circuit. The control circuit is coupled to control a switching of the switch in response the output of the comparator and the output of the feedback circuit to regulate the output of the power supply.02-03-2011
20120007573CIRCUIT AND METHOD FOR GENERATING POWER-UP SIGNAL - A power-up signal generation circuit includes a power-up signal generator configured to enable a power-up signal when a level of an external power voltage is higher than a target level, and a target level controller configured to change the target level in response to a current consumption signal indicating a current consumption of a system including the power-up signal generation circuit.01-12-2012
20110018517MULTI-LEVEL SIGNALING - A control circuit generates an output based on the first signal and the second signal by encoding the output to be a multi-state signal having at least three states. A magnitude of the multi-state signal generated by the controller varies depending on binary states of the first signal and the second signal. The controller utilizes the output (i.e., the multi-state signal) to control a switching circuit. A driver circuit receives the output generated by the control circuit. In one embodiment, the multi-state signal has more than two different logic states. The driver decodes the multi-state signal for generating signals to control switches in the switching circuit. One signal generated by the driver circuit is a pulse width modulation signal; another signal generated by the driver circuit is an enable/disable signal.01-27-2011
20110025287REGULATOR CIRCUIT - An object of the present invention is to reduce variations in the value of the output potential VDD of a regulator circuit including a bias circuit referring threshold voltage. The regulator circuit includes a bias circuit referring threshold voltage, an error amplifier, an output control circuit, and a feedback voltage divider. Further, the regulator circuit uses an n-type transistor and p-type transistor which offer small variations in the value obtained by Vthn+|Vthp|. The feedback voltage divider includes a diode-connected p-type transistor. The increase in the threshold voltage Vthn of n-type transistors leads to the increase in the threshold voltage Vthp of the p-type transistor. Therefore, the on resistance of the p-type transistor is reduced. As a result, the fluctuations in the output potential VDD is suppressed.02-03-2011
20100156377Systems and methods of increasing power measurement accuracy for power factor correction - Systems and methods for increasing power measurement accuracy for power factor correction (PFC) are disclosed. An exemplary method may include providing a PFC circuit for a power supply, the PFC circuit having a bulk capacitor connected to a rectified AC line. The method may also include measuring output load. The method may also include enabling AC wave skipping if the measured output load drops below a threshold value.06-24-2010
20120025798Voltage-modulated circuit device - A voltage-modulated circuit device uses a power source of a modulation circuit to acquire a predetermined trigger voltage through a voltage acquisition circuit and a step-down circuit to step down a voltage, and then a voltage amplification circuit amplifies the voltage by several times, such that the trigger voltage amplified by several times still falling within the range of predetermined voltage values triggers and conducts a switch circuit, and the power source of the modulation circuit can flow from an anode to a cathode in order to supply an electric power with a step-down voltage. With the design of triggering the conduction, the voltage of the modulation circuit can be modulated automatically to maintain the electric power supplied to the circuit device within the range of required voltage values, only if the trigger voltage has the predetermined voltage value.02-02-2012
20120153919Switching Mode Power Supply Control - A method for controlling a switching converter is disclosed whereby the switching converter is configured to convert an input voltage into an output voltage supplied to a load in accordance with a switching signal, The switching converter is configured to operate in a pulse width modulation mode or, alternatively, in a pulse frequency modulation mode. When operating in the pulse width modulation mode, generating, as the switching signal, a pulse width modulated (PWM) signal of a pre-defined constant switching frequency. The PWM signal has a duty cycle that is regulated such that the output voltage of the switching converter matches, at least approximately, a desired output voltage under the condition that the duty cycle being regulated such that it does not fall below a predefined minimum duty cycle. The output voltage is monitored and switched over to the pulse frequency modulation mode when the output voltage exceeds a predefined first threshold. The method further comprises, when operating in the pulse frequency modulation mode, monitoring the output voltage and generating, as the switching signal, a series of pulses of a predefined constant pulse length. A pulse is generated each time the output voltage falls to a predefined second threshold and monitoring the frequency of the switching signal and switching to the pulse width modulation mode when the frequency of the switching signal exceeds a predefined frequency threshold.06-21-2012
20110089924DUAL VOLTAGE HOT SWAP MODULE POWER CONTROL - A module hot swap circuit includes a low voltage-drop rectifier adapted to receive either positive or negative voltages of different absolute values. The rectifier is coupled to a power manager that provides dual startup/shutdown voltage thresholds and inrush current limiting. A detector prevents reverse current flow allowing the module to hold up during input voltage drop-outs.04-21-2011
20110089923Accurate Current Sensing Circuit with Ultra Low Voltage Supply - An integrated circuit includes a DC-DC converter, which includes an inductor; a first transistor coupled to the inductor and configured to pass an inductor current to the inductor; and a second transistor forming a current mirror with the first transistor. The integrated circuit further includes an operational amplifier. The operational amplifier includes a first input node and a second input node. The first input node is configured to couple to a drain of the first transistor when the first transistor is turned on, and decoupled from the drain of the first transistor when the first transistor is turned off. The second input node is coupled to a drain of the second transistor.04-21-2011
20110089922POWER SUPPLY CONTROL DEVICE, IMAGE FORMING APPARATUS, AND METHOD OF CONTROLLING POWER SUPPLY - A power supply control device includes an electrical power generating unit that generates electrical power and supplies the generated electrical power to an electronic device having a nonvolatile memory and a control unit; a switching unit that monitors a voltage of electrical power supplied to the electronic device, and switches such that, when the voltage is less than a predetermined threshold value, the electrical power is supplied to the control unit and is not supplied to the nonvolatile memory; and a capacitor that maintains, when the electrical power is switched to be supplied to the control unit, a voltage applied to the nonvolatile memory for a period of time during which writing of data to the nonvolatile memory can be completed.04-21-2011
20110089921POWER AMPLIFICATION DEVICE - According to one embodiment, a power amplification device configured to switching-amplify a high-frequency input signal into an output signal includes a feedback circuit, a subtractor, a comparator, an output tuning circuit, a constant voltage controlled power supply, and an amplifier. The feedback circuit is configured to output a portion of the output signal as a feedback signal. The subtractor is configured to output a difference between the input signal and the feedback signal as a error signal. The comparator is configured to generate an on/off pulse signal by comparing the error signal with a predetermined threshold voltage. The output tuning circuit is configured to resonate to a frequency of the input signal. The amplifier is configured to generate the output signal by switching-amplifying the input signal according to on/off of pulse signal, and output the output signal to the output tuning circuit.04-21-2011
20080278133IRREGULAR VOLTAGE DETECTION AND CUTOFF CIRCUIT USING BANDGAP REFERENCE VOLTAGE GENERATION CIRCUIT - An irregular voltage detection and cutoff circuit using a bandgap reference voltage generation circuit includes the bandgap reference voltage generation circuit, which generates a bandgap reference voltage from the power-supply voltage, a reference voltage generator, which generates a first reference voltage and a second reference voltage in the same voltage level as the bandgap reference voltage from the power-supply voltage, a voltage detector, which generates a detection voltage from the power-supply voltage, and a comparator, which generates a switching control signal that cuts off the power-supply voltage by comparing the first and second reference voltages with the detection voltage.11-13-2008
20120119720Load Transient Booster - A switching regulator comprises a PWM controller that controls switching of a power converter via a PWM control signal. The switching regulator detects load transients in the load driven by the power converter. Responsive to the detection of a load transient, the switching regulator resets a PWM clock synchronously with a fast clock operating at a higher frequency than the PWM clock. By doing so, the switching regulator beneficially responds more quickly to changes in the load than with conventional architectures that utilize only the slower PWM clock. This provides improved transient response without sacrificing power efficiency.05-17-2012
20120161737OUTPUT CIRCUIT - There is provided an output circuit for supplying an output current to a load coupled to an output terminal in response to an input signal. The output circuit includes an output transistor for supplying the output current to the output terminal, an output-drive circuit for driving the output transistor, a constant-current limiting circuit for generating a current control signal for limiting the output current to a predetermined current value, and a control circuit for implementing a control such that the output current is controlled on the basis of the current control signal if a voltage at the output terminal is at a predetermined voltage, or less after the input signal is supplied while the output transistor is driven by the output-drive circuit if the voltage at the output terminal is in excess of the predetermined voltage.06-28-2012
20100289473CURRENT SENSE CIRCUIT AND SWITCHING REGULATOR USING THE SAME - A current sense circuit for use with a switching regulator including a first transistor, connected to an inductor, configured to switch a current flowing through the inductor from a power supply; and a second transistor, connected to a node to which the inductor and the first transistor are connected, configured to be turned on during a part of an OFF period of the first transistor. The current sense circuit includes a current generator configured to generate a sense current corresponding to a current flowing through the first transistor; a hold circuit configured to output a voltage corresponding to the sense current during an ON period of the first transistor, and to hold and output the voltage corresponding to the sense current during the OFF period of the first transistor; and an output transistor configured to generate a current corresponding to the voltage output by the hold circuit.11-18-2010
20120313609CURRENT LIMITING CIRCUIT - A current limiting circuit includes a limit current setting unit that sets a value of a limit current for limiting an output current from a driver circuit connected to the current limiting circuit, the limit current value including a first acceptable value and a second acceptable value larger than the first acceptable value; an excess current detecting unit that detects when the output current from the driver circuit exceeds the first acceptable value; and a limit current adjusting unit that replaces the first acceptable value with the second acceptable value in a period when the output current detected by the excess current detecting unit exceeds the first acceptable value.12-13-2012
20120126772CURRENT MODE SYNCHRONOUS RECTIFICATION DC/DC CONVERTER - A current mode synchronous rectification direct current (DC)/DC converter according to the present invention includes: a soft start function unit (in FIG. 05-24-2012
20120126770MULTI-STAGE VOLTAGE REGULATING CIRCUIT WITH AUTOMATIC THERMAL COMPENSATION AND REGULATING METHOD THEREOF - A multi-stage voltage regulating circuit and method with automatic temperature compensation comprises a plurality of charge-pumps, a temperature compensator, a comparative unit and a control logic circuit; wherein, the temperature compensator detects the ambient temperature and outputs a reference voltage related to the ambient temperature, the comparative unit compares the voltage of the output power source to the reference voltage output by the temperature compensator and outputs a comparative signal based on the comparison, and the control logic circuit controls the charging/discharging operations of the charge-pumps based on the comparative signal and voltages of input power sources connected to said charge-pumps to automatically regulate the voltage of the output power source.05-24-2012
20120126771CIRCUITRY FOR DETECTING A TRANSIENT - Circuitry configured for detecting a transient is described. The circuitry includes an analog-to-digital converter that obtains a first voltage sample at a first time and a second voltage sample at a second time. The circuitry also includes a slope detector coupled to the analog-to-digital converter. The slope detector determines a first slope based on the first voltage sample and the second voltage sample. The circuitry further includes a threshold detector coupled to the slope detector. The threshold detector generates a first signal if the first slope exceeds a transient threshold.05-24-2012
20110181261POWER CONVERSION WITH ZERO VOLTAGE SWITCHING - A power converter constituted of: a control circuitry; a first electric coil; a first electronically controlled switch associated with the first electric coil and responsive to the control circuitry, the first electronically controlled switch arranged to charge the first electric coil responsive to a closed state of the first electronically switch; and a second electronically controlled switch arranged to present a substantially short circuit across the first electric coil when the second electronically controlled switch is closed, the second electronically controlled switch responsive to the control circuitry and not arranged to either charge or discharge the first electric coil.07-28-2011
20110181263OVER-CURRENT DETECTING APPARATUS FOR SWITCHING ELEMENT - An over-current detecting apparatus for a switching element (07-28-2011
20120212204SYSTEM AND METHOD FOR IMPROVING REGULATION ACCURACY OF SWITCH MODE REGULATOR DURING DCM - A controller for a switch mode regulator with discontinuous conduction mode (DCM) correction which includes a correction network and a modulator. The correction network detects a low load condition indicative of regulation error during DCM and asserts an adjust value indicative thereof. The modulator receives the adjust value and adjusts operation accordingly to improve regulation during DCM. The correction network receives or determines a regulation metric, such as periods between successive pulses of a pulse control signal, or a current sense signal indicative of load current, and compares the regulation metric with one or more thresholds for determining the level of adjustment. Adjustment may be made using one or more methods, such as adjusting pulse on-time, adjusting pulse off-time, adjusting frequency of operation, etc.08-23-2012
20120212205CONTROL SYSTEM OF DC TO DC CONVERTER - A control system of a DC to DC converter skips switching pulses according to the output of an overvoltage protection circuit. The overvoltage protection circuit includes an overvoltage threshold voltage control section that lowers an overvoltage threshold voltage when the pulse width has a minimum valve. The control system both improves the output voltage accuracy of the DC to DC converter under a light load and promotes a quick return to normal operation after an overvoltage protection operation under a heavy load.08-23-2012
20120133348AUDIO-SKIPPING OF A CONSTANT ON-TIME POWER CONVERTER - When the switching frequency of a constant on-time power converter decreases to a threshold, the power converter is switched from the original operation of triggering a constant on-time of a high-side switch responsive to the output voltage of the power converter reaching a valley point to the operation of triggering a constant off-time of the high-side switch responsive to the output voltage reaching a peak point, to thereby prevent the power converter from operating in an audio frequency range.05-31-2012
20100194368Current driving method and circuit - A circuit comprises an inductor, a load, and a controllable switching device arranged in either a first configuration: switchable between the load being bypassed and the inductor energised, and current flowing through the load, and the inductor discharging energy into the load; or, a second configuration: switchable between current being permitted to flow through the load, inductor and controllable switching device in series, energising the inductor, and the current flowing through the load, and the inductor discharging energy into the load. The circuit further comprises control means for controlling the switching device, a load current sensing resistor connected in series with the load, and a demand signal input. Monitoring means is arranged to monitor the demand signal and the voltages across the sense resistors, and generate a monitor signal. The control means is arranged to receive the monitor signal and to switch the switching device in response the monitor signal exceeding a predetermined threshold.08-05-2010
20120161736APPARATUS AND METHOD FOR INITIALIZING DC-DC CONVERTER - The present disclosure relates to an apparatus and method for initializing a DC-DC converter, and can stabilize an output voltage in an initial state, and prevent malfunction of a system control through initialization and high-efficiency DC-DC converters, by converting a variable voltage into a predetermined constant voltage and generating a reset signal for initializing a constant-voltage circuit so as to initialize the DC-DC converter and a control unit composed of the constant-voltage circuit, if the converted voltage reaches a target voltage, in an initialization DC-DC interval, and then converting the variable voltage into the predetermined constant voltage and outputting the converted voltage, in a high-efficiency DC-DC interval.06-28-2012
20110199063INTEGRATED CIRCUITS INCLUDING AN LC TANK CIRCUIT AND OPERATING METHODS THEREOF - An integrated circuit includes an inductor-capacitor (LC) tank circuit coupled with a feedback loop. The LC tank circuit is configured to output an output signal having a peak voltage that is substantially equal to a direct current (DC) voltage level plus an amplitude. The feedback loop is capable of determining if the peak voltage of the output signal falls within a range between a first voltage level and a second voltage level for adjusting the amplitude of the output signal.08-18-2011
20110204867Switching Power Supply Circuit - A switching power supply circuit comprises: a comparator for comparing a reference voltage, which is an output signal of a reference voltage generation circuit, with a feedback voltage, and outputting a set signal when a difference between the reference voltage and the feedback voltage exceeds a predetermined threshold value; an ON-time generation circuit for generating an ON-time signal for defining a period of time during which a switching element is kept ON; and a flip-flop circuit which turns on or off the switching element by the set signal and turns off or on the switching element by the ON-time signal. The reference voltage generation circuit has a first reference power supply for generating a first reference voltage, a second reference power supply for generating a second reference voltage (08-25-2011
20120176112CIRCUIT FOR SENSING LOAD CURRENT OF A VOLTAGE REGULATOR - A circuit for sensing load current of a voltage regulator. The circuit includes a power transistor and a minor transistor. A first transistor sizing circuit is coupled to the power transistor and is operable to control size of the power transistor based on a bias voltage of the power transistor, thereby regulating a first voltage for varying load conditions. The circuit also includes a feedback amplifier coupled to the power transistor and the mirror transistor. A transistor is coupled to the feedback amplifier and the mirror transistor. An analog to digital converter (ADC) is coupled to the transistor. A second transistor sizing circuit is coupled to the mirror transistor, the transistor, and the ADC. The second transistor sizing circuit is responsive to an output voltage to control size of the minor transistor, thereby ensuring that accuracy of output voltage sensed by ADC is not limited by ADC's resolution.07-12-2012
20120176111Power Control Circuit, Switching Power Converter, and Method for Reducing Noise and Switching Loss - Power control circuit with reducing noise and switching loss includes a first gate driver for driving a first switch, an additional gate driver for driving the first switch, and a managing circuit for controlling the first and the additional gate driver to drive the first switch according to a switching signal and turning off the additional gate driver according to a switching voltage on a first end of the first switch, wherein the first end of the first switch is coupled to a load, second end of the first switch is coupled to an input power source, a third end of the first switch is coupled to the first and the additional gate drivers.07-12-2012
20120074919POWER SUPPLY SYSTEM - Between a direct-current power source and a connection point where a resonance current flowing in an opposite direction from a main current joins the main current from the direct-current power source in a resonant converter, there is provided a current blocking circuit which blocks the resonance current toward the direct-current power source. In consequence, it is possible to prevent the reverse charging of the direct-current power source with the resonance current which realizes soft switching in the resonant converter.03-29-2012
20120182003System and Method for Controlling a Switched-Mode Power Supply - In an embodiment, a method of operating a switched-mode power supply includes producing an error signal based on a difference between a power supply output voltage and a reference voltage. A clock frequency is produced that is proportional to the error signal up to maximum frequency, and a sensed current signal is produced that is proportional to a current in switched-mode power supply. The error signal is summed with the sensed current signal to produce a first signal, and the first signal is compared to a first threshold. The method also includes producing a first edge of a drive signal at a first edge of the clock signal, and producing a second edge of the drive signal when the first signal crosses the first threshold in a first direction based on the comparing, where the second edge opposite the first edge.07-19-2012
20120256610Step Down Current Mirror for DC/DC Boost Converters - A low voltage current mirror design is used to control a high voltage boost converter. A high amperage reference current emanating from a high voltage inductor based DC-to-DC boost converter is mirrored to a low amperage output current. On-chip CMOS elements are used to measure and manipulate the output current, eliminating the need for a high precision, low resistance, external resistor. The measured and manipulated current is used to control the PWM duty cycle of an inductor based DC-to-DC boost converter, allowing for a lower cost solution in a high voltage, high current situation.10-11-2012
20120262142CONTROL DEVICE FOR BUCK-BOOST CONVERTER - A control device is disclosed, having a signal generating circuit and a mode decision circuit. The signal generating circuit is used to generate a first control signal and a second control signal according to an output voltage of a buck-boost converter. The first control signal is used to conduct a first switch and a second switch of the buck-boost converter. The second control signal is used to conduct a third switch and a fourth switch of the buck-boost converter. When the duty cycle of the first control signal is greater than a first predetermined value and the duty cycle of the second control signal is less than a second predetermined value, the mode decision circuit configures the signal generating circuit to generate the first control signal and the second control signal with substantially the same duty cycle.10-18-2012
20120299571SYSTEM AND METHOD FOR PROVIDING STABLE CONTROL FOR POWER SYSTEMS - System and method for providing stable control for power systems. According to an embodiment, the present invention provides an apparatus for providing one or more control signals for a power system. The apparatus includes an input terminal for receiving an electrical energy, which can be characterized by a first input voltage. The apparatus includes a control component that is configured to generate a first control signal based on at least information associated with the first input voltage. The apparatus additionally includes an output terminal for sending the first control signal. Moreover, the apparatus includes a timing component that is coupled to the control component. The control component is configured to process at least information associated with a first value of the first input voltage at a first time and a first reference voltage and to generate a second control signal.11-29-2012
20080315850SWITCHING REGULATOR - A switching regulator includes an inductor, first and second switches, a first rectifier to allow current flowing from a negative voltage output terminal to a connection node between the inductor and the first switch, a second rectifier to allow current flowing from a positive voltage output terminal to a connection node between the inductor and the second switch, a third switch, a first capacitor connected between the negative voltage output terminal and ground, a second capacitor connected between the positive voltage output terminal and ground, and a controller to control switching operations of the first, second and third switches to make each voltages at the negative and positive voltage output terminals to be corresponding predetermined voltages. The control circuit switches the first and second switches on/off simultaneously to make a sum of absolute values of voltages at the negative and positive voltage output terminals a predetermined voltage value.12-25-2008
20120268094Analog current limit adjustment for linear and switching regulators - Circuits and methods for dynamic adjustment of the current limit of a power management unit to avoid unwanted automatic interruption of the power flow have been disclosed. The invention can be applied to switched and linear DC-to-DC converters. The power management unit is automatically adjusted to the output resistance of a power source (including interconnect resistance). The invention maximizes the time and hence the power transferred from a power management unit to the system (including the battery, in case of battery operated systems). The input current is reduced, thus increasing the input voltage in case of a high voltage drop across the internal resistance including interconnections between power source and power management unit.10-25-2012
20120326689SWITCHING REGULATOR DEVICE AND METHOD WITH ADAPTIVE FREQUENCY FOLDBACK - A control circuit for a switching regulator includes a clock circuit, a pulsewidth modulation (PWM) circuit, and a reduction monitor. The clock circuit provides a clock signal at a variable frequency. The PWM circuit produces a drive signal of at least a first predetermined duration once every period of the clock signal. The reduction monitor controls the clock circuit to reduce the variable frequency in response to a sense signal that indicates that at least one of a voltage and a current is outside a limit during the first predetermined duration of said drive signal.12-27-2012
20110215783SEMICONDUCTOR DEVICE - A semiconductor device of the present invention includes an output transistor connected between a power supply terminal and an output terminal; a detection transistor generating a detection current that is proportional to a current flowing through the output transistor; a detection voltage generation unit generating a detection voltage based on a detection current; a protection transistor drawing a current from a control terminal of the output transistor to the output terminal according to the detection voltage; and a limited current generation circuit that generates a limited current that is obtained by converting a limit setting current that sets a current flowing through the output transistor in a protection state according to a variation of a threshold voltage of the protection transistor and a variation of the detection voltage with respect to the detection current, and supplies the limited current to a first terminal of the protection transistor.09-08-2011
20110210712AC or DC POWER SUPPLY EMPLOYING SAMPLING POWER CIRCUIT - A compact AC or DC input power supply device and method are described with an electrical power sampling circuit that includes a first switch for receiving the AC or DC voltage signal and capable of withstanding a high voltage input. A zero-crossing detector generates a zero-crossing detection ZCD signal when an input AC or DC voltage crosses or is above a zero voltage. A control circuit is coupled to the first switch for controlling the activation of the first switch from the generation of a zero-crossing detection signal. The first switch turns ON when the AC or DC input voltage is above a zero voltage, which safeguards the transfer of electrical energy to a first capacitor that is connected to the first switch. As a result, the selection of the first capacitor in the power supply device can be a low voltage capacitor.09-01-2011
20120081094REFERENCE VOLTAGE BASED EQUIVALENT SERIES RESISTANCE (ESR) EMULATION FOR CONSTANT ON-TIME (COT) CONTROL OF BUCK REGULATORS - The present invention uses a reference voltage that varies within a Pulse Width Modulation (PWM) cycle to generate the PWM signal. This allows for stability in the feedback of Constant On-Time (COT) control for buck controllers when low Equivalent Series Resistance (ESR) capacitors are used as the output capacitor. The reference voltage is adjusted using features of a PWM cycle in a voltage mode without using external inductor current information.04-05-2012
20120280670OFF-LINE CONVERTER WITH DIGITAL CONTROL - A power converter includes an input and an output. A regulation circuit is coupled between the power converter input and the power converter output. The regulation circuit is coupled to receive a feedback signal representative of the power converter output. The feedback signal has a first feedback state that represents a level at the power converter output that is above a threshold level and a second feedback state that represents a level at the power converter output that is below the threshold level. An oscillator is included in the regulation circuit that provides an oscillation signal that cycles between two states. The regulation circuit is coupled to be responsive to the oscillation signal and to a change between the first and second feedback states to enable or disable a flow of energy from the power converter input to the power converter output.11-08-2012
20120280669DYNAMIC CONTROL OF FREQUENCY COMPENSATION FOR IMPROVED OVER-VOLTAGE PROTECTION IN A SWITCHING REGULATOR - An error amplifier includes a difference amplifier providing an error signal representing a difference in voltage between a feedback signal and a reference signal. The error amplifier further includes a compensation circuit limiting the rate of change of the error signal. The compensation circuit includes a switch that when activated effectively removes a circuit portion from the compensation circuit. A switch signal indicates for the switch to be activated when the feedback signal exceeds the reference signal by a predefined amount.11-08-2012
20120091983STEP-DOWN SWITCHING REGULATOR - An output monitoring comparator outputs an ON signal when an output voltage becomes lower than a reference voltage. A pulse modulator generates a pulse signal at a predetermined level, an ON time-period from when the ON signal is outputted. A driver circuit alternately turns ON, after a dead time, a switching transistor and a synchronous rectification transistor, based on the pulse signal. A light load mode detector compares a switching voltage at a connection point of the switching transistor and the synchronous rectification transistor, and ground potential, and at timing at which the ON signal is outputted from the output monitoring comparator, when the switching voltage is higher than the ground potential, nullifies the ON signal.04-19-2012
20120286755DC-DC CONVERTER CIRCUIT - A DC-DC converter circuit includes a DC-DC converter IC that inputs, via an input terminal connected to a power supply input line, a direct-current voltage converted from an alternating-current voltage and supplied by the power supply input line. The DC-DC converter IC outputs a direct-current voltage having a value converted by operation of the DC-DC converter IC. The DC-DC converter IC is able to operate when a voltage of a specified threshold value or greater is input from an enable terminal. The DC-DC converter circuit also includes an enable control circuit that makes the voltage input to the enable terminal equal to the threshold voltage or greater when the direct-current voltage supplied from the power supply input line reaches a specified value.11-15-2012
20100181984Switching Control Circuit and Self-Excited DC-DC Converter - The switching control circuit comprises a switching control signal generation circuit that detects a change in ripples of the output voltage and-generates a switching control signal for the on/off control of the switching element to make the output voltage follow the target level; an overcurrent state detection circuit that generates a state signal indicating whether the output current is in an overcurrent state where the output current is equal to or greater than a predetermined current; and a delay circuit that delays the state signal for a same predetermined delay time at both of the times when the output current exceeds the predetermined current and when the output current falls below the predetermined current.07-22-2010
20120146610DISCHARGER AND DISCHARGER CONTROL METHOD - Upon detecting an external signal which instructs to stop discharge, an input voltage equal to or less than a set value for the prevention of overdischarge, or an output voltage equal to or more than a set value for the prevention of output of an overvoltage, a control unit (06-14-2012
20080231247Semiconductor device - To obtain a switching regulator which, when a load suddenly decreases, suppresses overshoot of output voltage without oscillating the output voltage is provided, even if being a current mode switching regulator, the present invention provides a semiconductor device for a switching regulator for converting input direct current voltage input from a direct current power supply to set direct current output voltage and outputting the output voltage from an output terminal, including: an overvoltage protection circuit for: comparing a target voltage with the output voltage at the output terminal; and making the output terminal in a discharge state when the output voltage exceeds the target voltage.09-25-2008
20080231246Current Detection Circuit, Load Drive Circuit, and Memory Storage - A stable high-precision current detection circuit capable of continuously detecting load current through a load with extremely reduced power loss. The current detection circuit has a power transistor and a current detection transistor that are fed with a common power supply voltage and a common switching signal. A buffer circuit is provided for supplying an idling current to the output node of the current detection transistor while realizing the same virtual potential at the output terminals of these transistors. Thus, the buffer circuit always functions as a class-A amplifier.09-25-2008
20080224680Voltage regulator - To enhance a safety of a voltage regulator, provided is a control circuit (09-18-2008
20080224679Regulator With Improved Load Regulation - A regulator to provide an output voltage of a constant level at an output node. In an embodiment, the regulator contains a pass transistor to provide a conductive path between a pair of terminals, with the resistance offered by the path being determined by a control voltage on a third terminal of the pass transistor and the conductive path coupling a first reference potential (e.g., power supply) to the output node. An amplifier generates the control voltage based on a difference of a reference voltage and a voltage proportionate to the output voltage. A control unit turns on a current source when the voltage at the output node is below the desired constant level and turns on a current sink when voltage at said output node is above the constant level, to quickly correct for any variations in the output voltage due to load changes.09-18-2008
20130099766Voltage Regulator with Optimal Efficiency Selection and a Master-Slave Zero Cross Detection Configuration - A voltage regulator includes a first phase power stage, a second phase power stage, and a controller. The first phase power stage includes a zero cross detection circuit configured to measure a current level for the first phase power stage, and to cause a diode emulation state in the first phase power stage when the current level is substantially equal to zero. The second phase power stage is in communication with the zero cross detection circuit, and configured to enter the diode emulation state in response to receiving a signal from the zero cross detection circuit. The controller is coupled to the first phase power stage and to the second phase power stage. The controller is configured to measure an output current of the voltage regulator and to activate the second phase power stage when the output current is above a first threshold current level.04-25-2013
20130169255REGULATOR POWER-ON-RESET WITH LATCH - This document discusses, among other things, apparatus and methods for providing a power-on-reset signal. An example apparatus can include a regulator configured to receive a supply voltage and to provide a regulated voltage at an output, and a power-on-reset (POR) circuit including a POR comparator. The POR circuit can be configured to provide an indication that the regulated voltage is below a threshold level using an output of the POR comparator and to disable the POR comparator when the regulated voltage is above the threshold level.07-04-2013
20130141070CONTROL SYSTEM AND METHOD FOR SHARED INDUCTOR REGULATOR - A control system and method for a shared inductor regulator. The regulator includes an inductor and multiple switches to selectively couple the inductor to output, reference and charge nodes. The charge node may be coupled to a battery. An input switch may be included to selectively couple the inductor to a source node. A controller controls the switches to regulate output voltage, charge current, and a source voltage when provided. The inductor current is sensed and used to regulate the output voltage, and to regulate either the charge current or the input voltage. When an external source provides sufficient power, the charging current is regulated. When the source reaches a maximum power set point, the input voltage is maintained at a minimum level. When the source provides insufficient power, the battery is used to add power or to provide sole power.06-06-2013
20130147455Power Management Method for Operating Electronic Device with Solar Energy - Power management method and apparatus for operating electronic devices with solar power is disclosed. Current-voltage characteristic of a solar system is measured by a controller. The maximum output power is determined accordingly. A power limiter is employed to limit the output power of solar system to be slightly below the maximum output power to prevent a sharp drop of the power caused by overdrawn of the power by the electronic device.06-13-2013
20100308786METHOD FOR DRIVING NON-LINEAR LOAD ELEMENTS - A method for driving a non-linear load element. On account of the non-linear interrelationship between the voltage and the current at the load element and the related non-linear dependence of the power loss on the quantities “voltage” and “current”, an adjustment of the switching speed only on the basis of the power loss in the switching element cannot be carried out with non-linear load elements without being confronted with undesirable switching losses and related electromagnetic noise fields. Therefore, the load current currently flowing in the load element is picked up in addition to the currently determined power loss in the switching element, and the switching speed of the switching element is controlled in dependence on the determined power loss and on the current picked up. The switching speed can be optimally adjusted when driving the non-linear load elements by means of PWM.12-09-2010
20120274301SWITCHED-MODE POWER SUPPLY - A ripple-control switched-mode power supply includes a control circuit to switch on/off a drive switching element. The control circuit includes a simulated voltage generation circuit that smoothes a voltage at a node connecting the drive switching element and an inductor and that generates a simulated voltage corresponding to an output voltage; a timer that measures a time corresponding to an input voltage and the simulated voltage; a voltage comparison circuit that compares a feedback voltage and a predetermined voltage; and a control pulse generation circuit that generates a control pulse having a pulse width corresponding to the time based on outputs from the timer and the voltage comparison circuit. The control circuit varies the pulse width of the control pulse in accordance with a variation in the input voltage to maintain a constant switching cycle.11-01-2012
20120274300SWITCHED-MODE POWER SUPPLY - Disclosed is a switched-mode power supply including an inductor which is connected between a voltage input terminal to which a DC voltage is input and an output terminal to which a load is connected, a driver switching element which intermittently feeds a current to the inductor and a control circuit which generates a control pulse according to a feedback voltage from output side and controls on/off of the driver switching element. The control circuit includes a voltage comparison circuit which compares the feedback voltage to a predetermined voltage and a pseudo ripple generator circuit which generates a pseudo ripple voltage having a predetermined amplitude, and the control circuit injects a ripple component in a transmission path of the feedback voltage based on the pseudo ripple voltage generated by the pseudo ripple generator circuit.11-01-2012
20100315056DATA RETENTION SECONDARY VOLTAGE REGULATOR - An integrated circuit device has a primary voltage regulator and an ultra-low power secondary voltage regulator. The ultra-low power secondary voltage regulator supplies voltage to certain circuits used for providing data retention and dynamic operation, e.g., a real time clock and calendar (RTCC) when the integrated circuit device is in a low power sleep mode. The primary voltage regulator provides power to these same certain circuits when the integrated circuit is in an operational mode.12-16-2010
20100315057METHOD AND RELATIVE FEEDBACK CONTROL LOOP OF A VOLTAGE CONVERTER - A feedback control method of a pulse width modulator (PWM) voltage converter may include generating a control voltage as a sum of an offset voltage and an error signal representing a difference between a scaled replica of a regulated output voltage of the voltage converter and a reference voltage, comparing the control voltage with a ramp signal, the comparing operation generating PWM driving signals for the voltage converter, comparing the regulated output voltage of the voltage converter with an overshoot threshold, and reducing the control voltage when the overshoot threshold is exceeded.12-16-2010
20130154597LATCHING OVER-CURRENT PROTECTION CIRCUIT AND METHOD - A load limiting circuit includes a transistor switch, for providing current to a load and a latching circuit having a control input, and a latch output driving the transistor switch. A current sensing transistor interconnects with the transistor switch, to sense current in excess of a threshold to the load. The current sensing transistor drives the control input to the latching circuit. An external controller may drive and monitor the control input. The controller may thus turn the transistor switch on and off, and be notified of an over-current condition. The latching circuit may turn the transistor switch off permanently. As well, the controller may attempt to set the load limiting circuit after an over-current condition.06-20-2013
20110285374METHOD AND APPARATUS FOR MAINTAINING A CONSTANT LOAD CURRENT WITH LINE VOLTAGE IN A SWITCH MODE POWER SUPPLY - A method and apparatus of reducing peak current variation with changing input line voltage in a switch mode power supply is disclosed. An example method includes sensing a current through a switching device of the switch mode power supply. A variable current limit threshold is generated, which increases from a first level to a second level during an on time of the switching device. The current is compared to the variable current limit threshold. A feedback signal representative of an output voltage of the switch mode power supply is sensed. The switching device is controlled in response to the feedback signal and said comparing the current to the variable current limit threshold.11-24-2011
20110309812SWITCHING REGULATOR WITH INPUT CURRENT LIMITING CAPABILITIES - A switching regulator includes a capacitor, a charge control circuit, a discharge detector, a switch circuit, and a feedback circuit. The charge control circuit charges and discharges the capacitor. The discharge detector has an input coupled to the capacitor to detect when the capacitor has discharged to a predetermined level to indicate an over-current condition. The switch circuit is coupled to receive an input voltage. The switch circuit is made conductive and non conductive by a switching signal for supplying an output voltage at a regulated voltage level. The duty cycle of the switching signal is reduced in response to an indication of an over-current condition. The feedback circuit is for controlling a discharge rate of the capacitor.12-22-2011
20120019225Control circuit and method for reducing output ripple in constant on-time switching regulator - The present invention discloses a control circuit for reducing output ripple in a constant on-time switching regulator and a method thereof, for controlling a power stage. The control circuit determines whether a zero current period wherein an output current is zero is longer than a threshold period, and switches the on-time period to a shorter period if it is longer, whereby the power stage operates according to the shorter period while still in the discontinuous conduction mode (DCM).01-26-2012
20130193943SWITCHED ARRANGEMENT FOR SWITCHED MODE SUPPLY - There is disclosed a switching stage comprising: a first switching path having at least one switching element for selectively connecting an input of the switching stage to an output of the switching stage; and a second switching path having at least one switching element for selectively connecting the input of the switching stage to the output of the switching stage, wherein the first and second switching paths are controlled such that a signal is selectively routed from the input of the switching stage to the output of the switching stage via the first and second switching paths in dependence on the current of the signal to be routed.08-01-2013
20130200872LOW POWER CURRENT COMPARATOR FOR SWITCHED MODE REGULATOR - A current comparator comprising a first NMOS transistor having a drain coupled to V08-08-2013
20120299570FIXED DEAD TIME PFC CONTROLLER - A fixed dead time PFC controller, comprising: an amplitude normalization circuit, used to generate a normalized signal according to a full-wave rectified input voltage; a comparator circuit, used to compare the normalized signal with a threshold voltage to generate a select signal, wherein the select signal exhibits a first state when the normalized signal is higher than the threshold voltage, and a second state when the normalized signal is lower than the threshold voltage; and a driving signal selection circuit, having a first input end coupled to a first driving signal, a second input end coupled to a second driving signal, a control end coupled to the select signal, and an output end for outputting a gate driving signal.11-29-2012
20120086422DCDC CONVERTER, SEMICONDUCTOR DEVICE, AND POWER GENERATION DEVICE - A DCDC converter includes a control circuit, a transistor in which switching is controlled by being supplied voltage output from the control circuit to a gate electrode of the transistor, a voltage conversion portion in which supply of input voltage is controlled by the switching of the transistor and output power commensurate with duty ratio of the switching of the transistor, and a detection circuit detecting the output power. Further, the control circuit includes a control signal generation circuit generating a control signal with a pulse voltage waveform and a selection circuit applying voltage of the control signal to the gate electrode in the case where current detected by the detection circuit is the same as or exceeds the threshold value and applying voltage for turning on the transistor to the gate electrode in the case where the current detected by the detection circuit falls below the threshold value.04-12-2012

Patent applications in class With threshold detection