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With ramp generator or controlled capacitor charging

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
20100033153PWM CLOCK GENERATION SYSTEM AND METHOD TO IMPROVE TRANSIENT RESPONSE OF A VOLTAGE REGULATOR - A pulse control clock generator for a voltage regulator including a comparator, a window circuit, a filter circuit, a ramp circuit, and a current circuit. The comparator compares a ramp voltage with a compensation voltage and provides a corresponding pulse control signal. The compensation voltage is indicative of output voltage error. The window circuit adds a window voltage to the compensation voltage to provide a hysteretic voltage. The filter circuit filters the hysteretic voltage to provide a filtered hysteretic voltage, such that a difference between the compensation voltage and the filtered hysteretic voltage is reduced in response to a load increase. The ramp circuit provides a repetitive ramp voltage which ramps between the filtered hysteretic voltage and the compensation voltage based on the pulse control signal. The current circuit increases a slope of the ramp voltage in response to the load increase.02-11-2010
20100033152PWM power converter using a multi-slope ramp signal to improve the transient response thereof - A ramp generator is provided to provide a multi-slope ramp signal for a PWM power converter. The ramp generator determines the slope turning points for the multi-slope ramp signal according to the error signal of the PWM power converter and thereby improve the transient response of the PWM power converter. Preferably, the slope turning point of the multi-slope ramp signal varies with the average of the error signal and is thus adaptive to the error signal and thereby the load condition.02-11-2010
20130033248Methods to Reduce Output Voltage Ripple in Constant On-Time DC-DC Converters - According to one aspect of the teachings herein, a DC-to-DC converter operates according to an advantageous constant on-time topology that reduces output voltage ripple during light load conditions. The converter produces an output voltage by driving high-side and low-side switches in an inductor-based switching circuit, and regulates the output voltage by varying the on-time of a low-side switch, while holding the on-time of the high-side switch constant. Advantageously, the converter shortens the on-time of the high-side switch during light load conditions, which reduces the output voltage ripple. Thus, the converter may be understood as using a first, constant on-time for the high-side switch during “normal” operations and a second, shorter on-time for the high-side switch during light load conditions.02-07-2013
20130043856CIRCUIT AND METHOD FOR GENERATING A RAMP COMPENSATION VOLTAGE FOR A SWITCHING REGULATOR - The present invention relates to a circuit and method of generating a ramp compensation voltage as might be used in a switching regulator. The ramp compensation voltage comprises: a charging current generating circuit configured to receive a switching signal having a frequency of fs, a duty cycle of D and a period of Ts, the charging current generating circuit generating a charging current in direct proportion to02-21-2013
20100045256DC/DC Converter and Slope Compensation Circuit Thereof - A slope compensation circuit includes a first differential pair circuit, a current mirror unit, a first operating current generation circuit, and a transconductance compensation circuit. The first differential pair circuit is connected to a first current source and receives a pair of differential oscillation signals to generate a pair of differential currents corresponding to the differential oscillation signals. The current mirror unit is connected to the first differential pair circuit and mirrors the differential currents. The first operating current generation circuit is connected to the current mirror unit and generates a first operating current including the differential currents. The transconductance compensation circuit stabilizes a quiescent operating point of the first operating current generation circuit and receives the differential oscillation signals to generate an output current multiple times the value of the first operating current.02-25-2010
20130038312MULTI-PHASE DC-DC POWER CONVERTER - A multi-phase DC-DC power converter including a pulse width modulation (PWM) controller and a plurality of output stage circuits is provided. The output stage circuits convert an input voltage into an output voltage. The PWM controller includes a PWM generation module, a ramp generator and a feedback circuit. The feedback circuit generates a trigger signal according to the output voltage and a ramp signal. The PWM generation module generates a PWM signal with a constant on time, and adjusts a duty cycle of the PWM signal according to the trigger signal, the input and output voltages, so as to control phase channels of the multi-phase DC-DC power converter in order.02-14-2013
20090206815SLOPE RATE COMPENSATION CIRCUIT, METHOD THEREOF AND PULSE WIDTH MODULATION BOOST CONVERTER CIRCUIT - A slope rate compensation circuit includes a source follower level-shift amplifier, a capacitor, a first resistor and a second resistor. The source follower level-shift amplifier includes a first transistor and a second transistor. The first transistor allows a first current to flow therein, the second transistor allows a second current to flow therein, and the first current increases with the second current. The capacitor is connected to the source terminal of the first transistor. The first resistor is connected to the source terminal of the second transistor. The second resistor allows a third current to flow therein, and the third current increases with the second current. The second resistor is related to the output voltage of the slope rate compensation circuit.08-20-2009
20130038311SYSTEM AND METHOD FOR SWITCHING VOLTAGE REGULATOR - A system and method for controlling ripple in an output voltage of a switching regulator is described. In one embodiment, the method includes providing a ramp circuit to selectively charge and discharge a ramp capacitor. The ramp capacitor provides a ramp voltage. The ramp voltage is selectively added to the output voltage to generate a summation voltage. The summation voltage is compared to a reference voltage to generate a control signal. An input voltage is coupled to an LC circuit based on the control signal. The LC circuit provides the output voltage. The input voltage is selectively coupled to the LC circuit when the ramp capacitor is selectively charged.02-14-2013
20130038313SWITCHING REGULATOR - A disclosed switching regulator includes a speed-up circuit for speeding up an operation of an error amplifier circuit during the time starting from when a switching element is turned OFF based on an output of an abnormality detection circuit, or starting from a fixed period of time after the switching element is turned OFF based on the output of the abnormality detection circuit, until the next time the switching element is again turned OFF based on an output of a PWM comparison circuit.02-14-2013
20130038310Constant frequency synthetic ripple power converter - A novel method to operate synthetic ripple switching power converters at constant frequency is presented. The method includes the generation of a clock signal and the summing of a ramp signal to a DC voltage reference to be compared to a synthetic ripple signal. The ramp signal is synchronous with the clock signal. A minimum on-time or minimum off-time type of control is implemented. The switching frequency is constant.02-14-2013
20100026268CONTROL METHOD FOR ADJUSTING LEADING EDGE BLANKING TIME IN POWER CONVERTING SYSTEM - A control method for adjusting leading edge blanking time in a power converting system is disclosed. The control method includes: receiving a feedback signal relative to a load connected to an output terminal of the power converting system; determining the leading edge blanking time to be a first value if the feedback signal has a magnitude about a first voltage; and determining the leading edge blanking time to be a second value if the feedback signal has a magnitude about a second voltage, wherein the first value is smaller than the second value, and the first voltage is greater than the second voltage.02-04-2010
20100066338VOLTAGE REGULATOR INCLUDING QUASI TRANSITION DIODE EMULATION MODE OF OPERATION - A voltage regulator includes an upper switching transistor connected between an input voltage node and a phase node. A lower switching transistor is connected between the phase node and ground. An output filter is connected between the phase node and an output voltage node. A PWM control circuit generates an PWM control signal responsive to a feedback voltage. An upper gate control circuit controls operation of the upper switching transistor responsive to the PWM control signal. A lower gate control circuit controls operation of the lower switching transistor responsive to the PWM control signal and a ramp voltage signal. The lower gate control circuit linearly increases a lower gate control signal from 0 to (1-D), where D=the duty cycle, to transition the voltage regulator for diode emulation mode of operation to synchronous mode of operation responsive to a first pulse in the PWM control signal.03-18-2010
20130069614POWER SUPPLY CIRCUIT AND POWER SUPPLY CIRCUIT WITH ADAPTIVELY ENABLED CHARGE PUMP - The present invention discloses a power supply circuit with adaptively enabled charge pump. The power supply circuit includes: a buck switching regulator switching at least one power switch therein to convert an input voltage to a middle voltage according to a control signal; a charge pump coupled to the buck switching regulator, wherein when the charge pump is enabled, the charge pump boosts the middle voltage to provide an output voltage higher than the middle voltage, and when the charge pump is disabled, the middle voltage is supplied as the output voltage; and a controller generating the control signal to control the switching regulator, and determining to enable or disable the charge pump according to a level of the input voltage.03-21-2013
20120217947DC-DC DOWN-CONVERTER WITH TIME CONSTANT COMPARISON REGULATION SYSTEM - A voltage converter device includes a voltage regulator having a supply terminal for receiving a supply voltage and an output terminal for providing a regulated voltage. A voltage multiplier is for receiving the regulated voltage and providing a boosted voltage higher in absolute value than the regulated voltage. The voltage multiplier includes circuitry for providing a clock signal that switches periodically between the regulated voltage and a reference voltage, and a sequence of capacitive stages that alternately accumulate and transfer electric charge according to the clock signal for generating the boosted voltage from the regulated voltage. The voltage regulator includes a power transistor and a regulation transistor each having a first conduction terminal, a second conduction terminal and a control terminal.08-30-2012
20090237060SWITCHING POWER SUPPLY CONTROL - A switching power supply controller includes a comparator to compare a feedback signal to a first limit and a second limit, one of which includes a ramp. Limit generators may be used to generate limit signals in response to power supply signals, control signals, and/or output signals. An error amplifier may be used to generate the feedback signal in response to an output signal and an input control signal. A switching power supply may alternatively include an oscillator that shifts the switching frequency in response to the input control signal.09-24-2009
20090237059Synchronous rectifying DC-DC converter - There is provided a dead time control method capable of recognizing a critical situation in which a commutating transistor cannot be turned on because of a temporary variation in an output voltage of a synchronous rectifying DC-DC converter and adaptively preventing the commutating transistor from being turned on. The synchronous rectifying DC-DC converter compares an output Voff of an error amplifier with a voltage Vt obtained by multiplying the peak voltage of a ramp by G2. When Voff becomes greater than or equal to Vt, the converter determines that dead time is insufficient to control the switching of the commutating transistor and prevents the commutating transistor from being turned on.09-24-2009
20090237058ADAPTIVE RAMP COMPENSATION FOR CURRENT MODE-DC-DC CONVERTERS - A current-mode controller comprises an inductance element, at least one semiconductor switch coupled to the inductance element, and a ramp compensator coupled to sense an indication of current through the inductance element and coupled to control the at least one semiconductor switch that senses current during on-time of the DC-DC converter, infers current during off-time of the DC-DC converter, and determines a slope compensation signal based on the sensed and inferred currents.09-24-2009
20080315853Dc-Dc Converter Controller Having Optimized Load Transient Response and Method Thereof - A power supply controller (12-25-2008
20100194371DC-DC CONVERTER AND SWITCHING CONTROL CIRCUIT - Disclosed a switching control circuit including: a first drive circuit to generate a drive signal for driving a driving switching element to flow current through an inductor for voltage conversion into on/off states; wherein the first drive circuit generates the drive signal so that a transition time of the drive signal in which the driving switching element shifts from an off state to an on state becomes longer than a transition time of the drive signal in which the driving switching element shifts from the on state to the off state.08-05-2010
20090174385Integrated soft start circuits - Various circuits, including DC/DC converters can include an integrated soft-start circuit. The integrated soft-start circuit includes a PMOS transistor configured to receive a reference signal and control the current to a bipolar junction transistor when the reference signal is in a first state. First and second NMOS transistors are included in the soft-start circuit, and receive the reference signal to turn off (to release from reset) when the reference signal is in the first state. A capacitor coupled in parallel with one of the NMOS transistors controls the soft-start signal. Various different transistors types can be used depending on the desired implementation.07-09-2009
20100253309ACCURATE CURRENT LIMIT FOR PEAK CURRENT MODE DC-DC CONVERTER - The present invention discloses an accurate current limit for peak current mode DC-DC converters by detecting the peak value of the slope compensation.10-07-2010
20120032661SWITCHING POWER SOURCE APPARATUS - A switching power source apparatus includes a high-side MOSFET 02-09-2012
20120032660SWITCHING POWER SOURCE APPARATUS - A switching power source apparatus includes a high-side MOSFET 02-09-2012
20090140712SELF-SUPPLY CIRCUIT AND METHOD FOR A VOLTAGE CONVERTER - An embodiment of a self-supply circuit, for a voltage converter that converts an input voltage into an output voltage and has a main switch and a controller, designed to control switching of the main switch for controlling the output voltage; the self-supply circuit is provided with: a charge accumulator, which is connected to the controller and supplies a self-supply voltage to the same controller; a generator, which supplies a charge current to the charge accumulator; and an auxiliary switch, which has a first conduction terminal in common with a respective conduction terminal of the main switch and is operable so as to control transfer of the charge current to the charge accumulator. In particular, the self-supply circuit is provided with a precharge stage, connected to the auxiliary switch, which carries out a precharging of an intrinsic capacitance of the auxiliary switch before a turning-off transient of the main switch ends.06-04-2009
20090189586SWITCHED-CAPACITOR SOFT-START RAMP CIRCUITS - Methods and apparatus for a switched-capacitor soft-start ramp generator circuit are described. In an example, an apparatus to provide a soft-start voltage is described, comprising a first capacitor, a feedback circuit to increase a reference voltage based on an output voltage, a second capacitor, having a capacitance value greater than a capacitance value of the first capacitor, a first device to couple and decouple the first capacitor to the reference voltage and a second device to couple and decouple the first capacitor to the second capacitor.07-30-2009
20100001706CONVERTER HAVING PWM RAMP ADJUSTABLE IN DISCONTINUOUS MODE OPERATION - A ramp adjustment circuit for a voltage converter including a gate driver for controlling series connected high- and low-side switches connected across DC voltage and coupled at an output node connected to a load through an inductor such that the converter operates in a continuous conduction mode (CCM) or a discontinuous conduction mode (DCM). The circuit includes a first current generating circuit for providing a first current signal for generating a first ramp signal; a second current generating circuit for providing a second reduced current signal for generating a second ramp signal having a reduced slope when the first current generating circuit is disabled and the second current generating circuit is enabled; and a circuit for enabling the first current generating circuit and disabling the second current generating circuit when the converter is in CCM and enabling the second current generating circuit and disabling the first current generating circuit when the converter is in DCM thereby providing the first current signal when the converter is in CCM to provide the first ramp signal and providing the second reduced current signal when the converter is in DCM to provide the second reduced slope ramp signal.01-07-2010
20090167276Soft-Start Circuit and Method Thereof - A soft-start circuit and a method thereof are described. The circuit includes an amplifier and a voltage ramp generator. The amplifier has a first input end, a second input end, an output end, and a power source control end. The first input end is coupled to a reference voltage. The second input end is coupled to a feedback voltage. The output end outputs an output voltage, and the feedback voltage corresponds to the output voltage. The voltage ramp generator is coupled to the power source control end, and generates a ramp-up voltage. When the ramp-up voltage is lower than a threshold value, the output voltage rises with the ramp-up voltage. When the ramp-up voltage is not lower than the threshold voltage, the output voltage remains at a stable value. A surge current occurring during smooth soft-start or even in operation is thus prevented.07-02-2009
20090146632SOFT START OF A SWITCHED SECONDARY CONTROL CIRCUIT FOR A SWITCHED MODE POWER SUPPLY - Usually when switched secondary control is used to regulate output voltages in a flyback converter, high peak currents through the secondary switch occur during startup. Traditional soft-start methods cannot be applied to limit these peak currents. With the inventive control circuit and method, current limiting during startup is achieved by measuring the magnetic flux in the fly-back transformer, and by advancing the time instant at which current flow through the secondary switch (06-11-2009
20120112721SYNTHETIC RIPPLE REGULATOR WITH FREQUENCY CONTROL - A synthetic ripple regulator including frequency control based on a reference clock. The regulator includes an error network, a ripple detector, a combiner, a ripple generator, a comparator network and a phase comparator. The error network provides an error signal indicative of relative error of the output voltage. The ripple detector provides a ramp control signal based on the input and output voltages and a pulse control signal. The combiner adjusts the ramp control signal based on a frequency compensation signal to provide an adjusted ramp control signal. The ripple generator develops a ripple control signal based on the adjusted ramp control signal. The comparator network develops the pulse control signal to control switching based on the error signal and the ripple control signal. The phase comparator compares the pulse control signal with the reference clock and provides the frequency compensation signal.05-10-2012
20110062932DC/DC CONVERTER HAVING A FAST AND ACCURATE AVERAGE CURRENT LIMIT - In order to overcome the three main obstacles to obtaining a fast and accurate average current limit in a DC/DC converter, three distinct improvements are provided which can work in concert to achieve the goal. Each of the three parts comprises significant new improvements, and their use together to create an average current limit is also believed to be novel. The first improvement relates to providing a bias signal control configured to apply a variable DC bias signal to the compensation ramp signal generated in the DC/DC converter so that the compensating ramp signal is biased to zero at the end of each ON-time for each cycle so that the peak current limit is independent of the duty cycle of the pulse width modulation signal during current limit conditions. A second improvement relates to modulating the clamp voltage that establishes the peak current limit as a function of ripple of the inductor current for each cycle of the pulse width modulation signal so as to reduce or cancel the effect of the inductor ripple current on the average output current during current limit conditions. The third improvement relates to adjusting the frequency of the pulse width modulation signal during current limit conditions as a function of both the input voltage and the output voltage of the DC/DC converter.03-17-2011
20110062931DC-DC CONVERTER - Provided is a DC-DC converter including a soft start circuit capable of prolonging a soft start time without increasing a capacitance used in the soft start circuit. A soft start is implemented by gradually increasing a limiting level of an inductor current or a reference voltage. The soft start time is adjusted by varying a frequency of CLOCK signals supplied to switch circuits. The soft start time may be prolonged without increasing a chip size because the capacitance does not need to be increased to prolong the soft start time.03-17-2011
20090278521Power Supply Device And Electronic Appliance Therewith - In a power supply device of the present invention, a clamp circuit increases the upper limit value of an error voltage stepwise after the device is started up. This makes it possible to shorten the rise time of an output voltage and to reduce the maximum current at start-up.11-12-2009
20090261798Systems and Methods for Fast Switch Turn On Approximating Ideal Diode Function - A switching circuit approximating the fast switching characteristics and small forward voltage drop of an ideal diode is provided. The switching circuit may include a voltage multiplier circuit, a reservoir capacitor and a pull up switch configured to be coupled to the control terminal of a semiconductor switch.10-22-2009
20090261797SWITCHING REGULATOR - Provided is a switching regulator which is capable of reducing soft start time when being activated, and prolonging battery life. The switching regulator has a configuration in which a clamp circuit for clamping a reference voltage is provided in a soft start circuit, and a predetermined period of time since the switching regulator has been activated is divided into a plurality of segments to increase the reference voltage with different slopes for each of the plurality of segments. At an early stage of the activation, the reference voltage is set to be low for preventing an inrush current from a power source, and thereafter, a rate of increase in reference voltage is gradually increased, to thereby reduce the soft start time.10-22-2009
20080278135BOOTSTRAP CLAMPING CIRCUIT FOR DC/DC REGULATORS AND METHOD THEREOF - A clamping circuit of a DC/DC regulator includes a reference current generator to generate a reference current. The reference current can be based upon a specified maximum voltage across a bootstrap capacitor of the DC/DC regulator. The clamping circuit also includes a current generator that generates a current based on the voltage across the bootstrap capacitor. The current generated by the current generator is compared to the generated reference current. Based on the comparison, the voltage across the bootstrap capacitor is regulated. By regulating the voltage across the bootstrap capacitor based on current, rather than based directly on the voltage across the capacitor, the design of the clamping circuit is simplified compared to voltage-based implementations.11-13-2008
20100201337Voltage regulator for low noise block - A voltage regulator comprises first and second capacitors and regulation means arranged to provide a respective regulated charging current from an input terminal to each of the capacitors. The regulation means comprises at least one device through which at least a portion of the respective charging current to at least one of the capacitors is supplied. The device is controllable with a control signal to regulate current flow through the device. The regulation means further comprises control signal supply means connected to the output terminal and arranged to provide said control signal to the device, the control signal being dependent upon voltage at the output terminal such that current flow through the device is regulated according to the voltage at the output terminal.08-12-2010
20080265857INTEGRATED FET SYNCHRONOUS MULTIPHASE BUCK CONVERTER WITH INNOVATIVE OSCILLATOR - A power conversion system, preferably a buck converter, having (i) an oscillator, (ii) a pulse width modulator, (iii) and a nonoverlap clock generator and level shifter, wherein the improvement comprises the elimination of an external resistor divider is described. The buck converter can convert input voltage ranging from approximately 3V to 5V down to approximately 0.7-1.0V, 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V without the use of resistor dividers. The voltage input identifiers select one of the possible output settings for flexibility and accuracy. The integrated field emitting transistors can provide a continuous current of at least 6 A. Additionally, peak current mode and an oscillator enable multiphase operation, up to ten buck converters, for up to 60 A output current. The multiphase operation reduces the output inductor size, and number of bulk capacitors. Moreover, the multiphase operation yields higher efficiency and provides high transient response for demanding applications.10-30-2008
20110006747STEP-UP CIRCUIT AND STEP-UP CIRCUIT DEVICE - A step-up circuit comprises a rectifier element 01-13-2011
20110006746SOFT-START CIRCUIT AND METHOD FOR A SWITCHING REGULATOR - A soft-start circuit for a switching regulator includes a signal generator and a scaling circuit coupled to the signal generator. During soft-start, the signal generator provides a ramp signal for the switching regulator such that the output voltage of the switching regulator changes from a residual voltage toward a target level. When soft-start is triggered, the scaling circuit provides a scaling voltage depending on the residual voltage, to shift the level of the ramp signal and consequently shorten the soft-start time of the switching regulator.01-13-2011
20090160416DC-DC CONVERTER - A DC-DC converter generates an optimal slope compensation voltage in response to input and output voltages, thus capable of maintaining its operational stability even when a dynamic range of the output voltage is widen. The DC-DC converter compares an error voltage corresponding to a difference between a feedback voltage of the output voltage and a reference voltage with a ramp signal whose voltage level corresponds to a current detection signal, so as to configure an off-timing of an output transistor. A slope of the ramp signal is configured so that the ramp signal is proportional to a difference between the output voltage and the input voltage. A slope compensation circuit for generating the ramp signal includes an adding circuit for generating a slope controlling electric current corresponding to a voltage in which a voltage corresponding to the input voltage is subtracted from a voltage corresponding to the output voltage, and a capacitor electrically charged with the slope controlling current.06-25-2009
20090015231DIGITAL PWM MODULATOR WITH FAST DYNAMIC RESPONSE AND FINE RESOLUTION - A pulse width (PWM) controller for a voltage converter having at least one switch, an Analog to Digital Converter (ADC) circuit for digitizing inputted state variables including a feedback voltage from an output of the voltage converter and a reference voltage for setting the output of the voltage converter and providing a digital error signal, and a Proportional Integration and Derivation (PID) circuit receiving the digital error signal and providing a digital duty cycle signal. The controller including a Digital to Analog Converter (DAC) circuit for converting the digital duty cycle signal into an analog DAC output signal; and a comparator circuit for comparing a first signal including the DAC output signal with a reference signal for generating a pulse width modulated control signal for controlling the switching of the at least one switch of the voltage converter.01-15-2009
20110221417POWER SUPPLY APPARATUS AND POWER SUPPLY CONTROL METHOD - A power supply apparatus includes a detector configured to detect a peak of a transmission signal, a determination unit configured to determine a timing when a change of a variable voltage which is output from the apparatus and which corresponds to the detected peak of the transmission signal is started in accordance with a voltage value corresponding to the peak and a change rate of the variable voltage, a generation unit configured to generate a variable voltage control signal used to start the change of the voltage at the determined timing, and an output unit configured to output a voltage in accordance with the generated variable voltage control signal.09-15-2011
20090021232Switching Regulator - A switching regulator according to the invention includes a resistor (R01-22-2009
20090243580METHOD OF FORMING A POWER SUPPLY CONTROLLER AND STRUCTURE THEREFOR - In one embodiment, a power supply controller is configured to select either an error signal or a variable reference signal to control an on-time of the switching output signal of the power supply controller.10-01-2009
20100148742VOLTAGE REGULATOR - An output voltage of a voltage regulator is set to within a prescribed voltage range in a short time. The voltage regulator comprises: an amplifier (AMP) that amplifies a difference between a reference voltage and a voltage proportional to an output voltage; an NMOS transistor (MN06-17-2010
20090315530PULSE CONTROLLED SOFT START SCHEME FOR BUCK CONVERTER - A pulse controlled soft start scheme for a buck converter using a low value of on-chip capacitor is disclosed. In one embodiment, a system for generating a ramped reference voltage to soft start a buck converter, includes a current source coupled to a positive power supply, a capacitor coupled to a ground, a pass transistor device coupled to the current source and the capacitor in series, and a control pulse generator for generating a control pulse forwarded to the pass transistor device. The ramped reference voltage forwarded to the buck converter includes a voltage across the capacitor. The control pulse regulates a flow of a current from the current source to the capacitor via the pass transistor device for generating the ramped reference voltage.12-24-2009
20090273330MERGED RAMP/OSCILLATOR FOR PRECISE RAMP CONTROL IN ONE CYCLE PFC CONVERTER - A one cycle power factor correction converter circuit comprising a switch for controlling a DC output voltage of the converter circuit, the switch being switched by a drive signal having a frequency determined by a clock signal; the converter circuit being provided with a DC input voltage and producing the DC output voltage, the DC input voltage being rectified from an AC input; a controller circuit for controlling an on-time or off-time of the switch to set the output voltage and to achieve power factor correction at the AC input; the controller circuit comprising an error amplifier receiving a feedback voltage from the output of the converter circuit and a reference voltage and producing an error signal; a ramp generator receiving the error signal and generating a first ramp signal by integrating a signal related to the error signal; a pulse width modulation circuit receiving the first ramp signal and a signal related to the error signal and producing a pulse width modulated signal by comparing the first ramp signal and the signal related to the error signal; the pulse width modulated signal determining the on-time or off-time of the switch to control the output voltage with power factor correction; further comprising a circuit for terminating the first ramp signal when a predetermined inequality exists between the first ramp signal and a reference signal and for developing the clock signal from the first ramp signal.11-05-2009
20100176784POWER SUPPLY CIRCUIT AND SEMICONDUCTOR DEVICE FOR USE THEREIN - A power supply circuit has: a DC/DC converter (M07-15-2010
20100019751ADAPTIVE FREQUENCY COMPENSATION FOR DC-to-DC CONVERTER - One embodiment of the invention is a compensation circuit that includes a comparator that is coupled to receive a reference voltage. The compensation circuit can also include a capacitance coupled to receive a feedback voltage associated with an output voltage of a converter. Furthermore, the compensation circuit can include an adjustable resistance that is coupled to the capacitance and to the comparator.01-28-2010
20090251120HIGH VOLTAGE POWER SUPPLY - There is provided a high voltage power supply capable of reducing voltage stress of a voltage multiplying device. The high voltage power supply includes: a power converter switching on/off and converting an input direct current power into a direct current power having a preset voltage level; and a voltage multiplier including a first multiplying cell multiplying the voltage level of the direct current power from the power converter, wherein the first multiplying cell includes: first and second capacitors charging the direct current power from the power converter, respectively; a first diode providing a path for transferring the direct current power when the power converter is switched off; and a second diode providing a path for transferring the direct current power when the power converter is switched on.10-08-2009
20110057638PULSE WIDTH MODULATION REGULATOR IC AND CIRCUIT THEREOF - A pulse width modulation regulator IC is provided for controlling a duty cycle of at least one switch to convert one input voltage signal into an output voltage. An input pin is provided for receiving an input signal different from the input voltage signal. The input signal has a lasting time substantially the same as the time that input voltage signal situated at a high level, but the waveforms of the two signals are different. The input signal is converted into a square wave signal by a conversion unit, and a PWM signal is generated by a PWM controller according to the square wave signal to control the duty cycle of the switch. Therefore, the input pin can be saved by adjusting an internal or external circuit of the IC for the usage of the different kinds of input signals without increasing the number of input pins of the IC.03-10-2011
20090072808START-UP CIRCUIT AND METHOD FOR HIGH VOLTAGE POWER DISTRIBUTION CIRCUIT - A start-up circuit for a high voltage power distribution circuit includes a transistor, a current source which generates ramped current, an operational amplifier which is connected between the current source and the transistor and controls the transistor, a capacitor which is fed the generated ramped current from the current source and is charged by the generated ramped current, the capacitor being connected to the non-inverting input of the operational amplifier, and a feedback capacitor connected from the transistor output to the non-inverting input of the operational amplifier, which is fed the generated ramped current from the capacitor and is discharged. The transistor is fully enabled when the feedback capacitor is fully discharged.03-19-2009
20110031951FREQUENCY MODULATION CONTROL OF A BUCK-BOOST POWER CONVERTER - A control circuit and method are proposed to generate a control signal to operate a buck-boost power stage of a buck-boost power converter to convert an input voltage to an output voltage. The control circuit and method detect the output voltage to generate an error signal, control the frequency of two ramp signals according to the error signal, generate two pulse width modulation signals according to the error signal and the two ramp signals, and generate the control signal according to the two pulse width modulation signals. When the loading of the buck-boost power converter transits from heavy to light, the frequency of the two ramp signals is decreased to improve the efficiency of the buck-boost power converter. The peaks and valleys of the two ramp signals may be adjusted by signals related to the input voltage and the output voltage.02-10-2011
20090108826MODULATOR WITH LINEAR PERIOD STRETCHING CAPABILITY - A modulator for use with a voltage regulator includes an input for receiving an input voltage, an output for providing a periodic triangular wave form and at least one input for receiving an indication that the voltage regulator is in a discontinuous current mode of operation. The circuitry within the modulator generates the periodic triangular wave form responsive to the input voltage and the indication that the voltage regulator is in the discontinuous current mode of operation. The circuitry further continuously increases a period of the periodic triangular wave form responsive to a decreased load in a discontinuous current mode of operation of the voltage regulator.04-30-2009
20100320991DC/DC CONVERTER AND DC/DC CONVERTER CONTROL METHOD - A DC/DC converter includes a first comparator configured to compare an output voltage to a reference voltage; a pulse generator circuit configured to generate a pulse signal when triggered by an output signal from the first comparator; a first switch circuit configured to open and close on the basis of the pulse signal; an output voltage generator configured to generate the output voltage on the basis of an input voltage supplied via the first switch circuit; a delay generator circuit configured to delay the output signal from the first comparator before outputting; and an error amplifier configured to control a delay time of the delay generator circuit on the basis of a potential difference between the output voltage and the reference voltage.12-23-2010
20100225292CONTROL CIRCUIT FOR DC-DC CONVERTER, DC-DC CONVERTER, AND METHOD FOR CONTROLLING DC-DC CONVERTER - A DC-DC converter control circuit includes: a slope signal generation circuit that generates a reference voltage by superimposing a slope voltage onto a standard voltage; a comparator that performs comparison of the reference voltage with an output voltage and generates a signal according to a result of the comparison; an oscillator that generates a pulse signal with a substantially constant cycle; and a control signal generation circuit that generates a control signal that turns on a switch based on a comparator output signal and turns off the switch based on the pulse signal.09-09-2010
20100026267SINGLE INDUCTOR MULTIPLE OUTPUT SWITCHING DEVICES - Single inductor multiple output (SIMO) switching devices with efficient regulating circuits. The SIMO switching device includes a plurality of time division multiplexing (TDM) switches for switching current through an inductor of the SIMO switching device. The plurality of TDM switches produces a plurality of outputs. The SIMO switching device further includes an error calculation circuit operatively coupled to the plurality of outputs for determining a calculated error from the plurality of outputs; a time slot generation circuit for controlling the plurality of TDM switches according to the calculated error; and a pulse width modulation (PWM) control circuit operatively coupled to the time slot generation circuit for controlling a plurality of PWM switches of a switching stage of the SIMO switching device in a continuous conduction mode (CCM) of operation. The PWM switches are controlled according to the time slots generated by the time slot generation circuit.02-04-2010
20100039088INTERLEAVED SLAVE SWITCHING CIRCUIT FOR DISCONTINUOUS MODE PFC CONVERTER - A slave switching circuit for a master-slave PFC converter is disclosed. The slave switching circuit includes a phase-detection circuit coupled to detect a master-switching signal and a slave-inductor signal for generating a start signal and a phase-lock signal. The start signal is coupled to enable a slave-switching signal. The slave-switching signal is coupled to switch a slave inductor. An on-time-adjust circuit is used to adjust the on-time of the slave-switching signal in accordance with the phase-lock signal. The slave-inductor signal is correlated to the demagnetization of the slave inductor. The phase-lock signal is coupled to minimize the period between the disablement of the slave-inductor signal and the enablement of the start signal.02-18-2010
20110248696METHOD OF FORMING A POWER SUPPLY CONTROLLER AND STRUCTURE THEREFOR - In one embodiment, a power supply controller forms a compensation current modulates a value of the feedback signal responsively to a value of a timing control signal used to form a clock signal.10-13-2011
20120119721CIRCUIT ARRANGEMENT INCLUDING VOLTAGE SUPPLY CIRCUIT - A circuit arrangement comprising a first semiconductor switching element, which has a load path and a drive terminal. A voltage supply circuit, is provided including an inductance connected in series with the load path of the first semiconductor switching element, and a capacitive charge storage arrangement, which is connected in parallel with the inductance and which has a first and a second output terminal for providing a supply voltage.05-17-2012
20090027029Load control unit - A load control unit for controlling the supply of an electric power to a load from battery in accordance with a pulse-width modulation control includes: a reference voltage generating unit; a first charging/discharging unit; a second charging/discharging unit connected in series to the first charging/discharging unit to charge and discharge in reverse to those of the first charging/discharging unit; a first comparing unit that compares the voltage of the first charging/discharging unit with the reference voltage and switches between the charge and discharge of the first charging/discharging unit to generate a triangle wave; and a second comparing unit that compares a divided voltage by dividing the voltage of the battery with the voltage of the triangle wave generated by the first comparing unit to generate a PWM pulse. The ratio of capacities between the first and second charging/discharging units approximates to the ratio of resistances for obtaining the divided voltage.01-29-2009
20090027028PULSE WIDTH MODULATED CONTROLLER APPLIED TO SWITCH-TYPE VOLTAGE REGULATOR - A PWM controller applied to switch-type voltage regulator includes an error amplifier, a soft-start control circuit, a compensating load and a comparator. The error amplifier receives a reference voltage signal and a feedback voltage signal and outputs an error current signal according to the received feedback voltage signal and the reference voltage signal. The soft-start control circuit outputs a compensating current signal according to at least one soft-start control signal. The compensating load receives the error current signal and the compensating current signal, and outputs a compensating signal. The comparator receives a ramp signal and the compensating signal, and outputs a pulse width modulated (PWM) signal. When a supply voltage rises, the error amplifier is compensated with a preset soft-start compensating current to a circuit common ground VSS, so that the error signal slowly rises during the soft-start control process. Therefore, the function of soft-starting is effectuated.01-29-2009
20100244803Switching Converter with Plural Converter Stages having Calibrated Current Uptake - A switching converter according includes a control arrangement to furnish a control signal dependent on the output voltage, as well as a first and at least one second converter stage. Each converter includes an inductive storage element, a ramp signal generator to furnish a signal having a ramp slope, a pulse width modulator which receives the control signal and the ramplike signal and which furnishes a pulse width modulated signal, and a driver circuit which receives the pulse width modulated signal and the input voltage and which applies the input voltage to the inductive storage element depending on the pulse width modulated signal. The ramp slope of the ramplike signal of the at least one second converter stage is adjustable. The ramp signal generator of the second converter stage receives a calibration signal which depends on the inductance of the inductive storage element of the first converter stage.09-30-2010
20090108825CHARGING CIRCUIT FOR A VEHICLE CHARGER - A charging circuit for a vehicle charger includes a front high-voltage protective circuit, a rear high-voltage protective circuit, a first filtering circuit, an over-voltage protective circuit, a high frequency step-down switching regulator, a second filtering circuit, a frequency modulation circuit, a reference voltage input circuit, a sampling circuit, a short-circuit protective circuit and two charging interfaces. The front high-voltage protective circuit connects to a vehicle DC power, the first filtering circuit connects the front high-voltage protective circuit to the switching regulator, the second filtering circuit connects to an output point of the switching regulator to the rear high-voltage protection circuit, the frequency modulation circuit connects to a second input point of the switching regulator, the third input point of the switching regulator connects to the reference voltage input circuit, the short-circuit protective circuit connects the second filtering circuit to the fourth input point of the switching regulator, the sampling circuit connects the second filtering circuit to the fifth input point of the switching regulator, the rear high-voltage protection circuit connects to the two charging interfaces. For the unique design, the charging circuit for a vehicle charger has a short-circuit protective function and provides two charging interfaces.04-30-2009
20080203991DC-DC Converter that Includes a High Frequency Power MESFET Gate Drive Circuit - A DC-DC converter that includes a high frequency power MESFET gate drive circuit is provided. The gate drive circuits are intended to be used in switching regulators where at least one switching device is an N-channel MESFET. For regulators of this type, the gate drive circuits provide gate drive at the correct voltage to ensure that MESFETs are neither under driven (resulting in incorrect circuit operation) nor over driven (resulting in MESFET damage or excess current or power loss).08-28-2008
20100213914CORRECTING PRE-BIAS DURING TURN-ON OF SWITCHING POWER REGULATORS - Rather than operating in asynchronous mode during turn-on ramps, a switching power regulator system may be configured to synthesize a digital waveform, which may protect against a pre-bias condition and maintain the desired ramp-up time and rate. The desired turn-on ramp may be generated digitally by counter logic, beginning with an initial value and incrementing at a programmed rate until a digital value equivalent to the desired output voltage is reached. When a pre-bias condition is not present, the output of the digital ramp generator may control a digital-to-analog converter (DAC), which may be configured to generate the reference voltage for the power regulator. To correct for a pre-bias condition, the pre-bias output of the power regulator may be measured prior to turn-on, using an analog-to-digital converter. The digital pre-bias value may be used to control the DAC until the value of the digital waveform generated by the ramp generator reaches the pre-bias value.08-26-2010
20080218145Current-mode DC-to-DC-converter - A current-mode DC-to-DC converter operating in a high frequency is disclosed. The current-mode DC-to-DC converter includes an inductor, a power switch, an oscillator, an adder without internal feedback loop, an error amplifier, a comparator, a compensation unit and a driver. The adder adds a ramp signal from the oscillator directly to a voltage signal relative to a current flowing through the power switch and generates a sum signal based upon match between internal components in the oscillator and the adder.09-11-2008
20110187342NON-LINEAR COMPENSATION RAMP FOR CURRENT MODE PULSE WIDTH MODULATION - A current mode direct current-to-direct current (DC-to-DC) voltage regulator controls its output voltage using a pulse width modulation (PWM) circuit that employs a non-linear compensation ramp. By employing such a PWM circuit, the output voltage can be controlled more robustly over a wider range of operating conditions.08-04-2011
20110148382Start-Up Supply - In one embodiment, an apparatus includes a transistor having a gate, a drain, and a source. The drain is coupled to receive an AC power supply signal. A component is coupled between an output node and the gate of the transistor. The component couples an output voltage from the output node to charge a gate-source capacitor during a first portion of the AC power supply signal. The transistor is configured to turn on during a second portion of the AC power supply signal to send a charge to the output node where the charge is used to power a circuit of a power supply.06-23-2011
20090033305PWM/PFM Control Circuit and Switching Power Supply Circuit - A PWM/PFM control circuit has a differential time generating means for forming a differential time signal representing a differential time corresponding to a difference between the pulse width of a PWM control signal and the pulse width of a PFM control signal on condition that the pulse width of the PWM control signal is smaller than the pulse width of the PFM control signal, and the oscillation frequency of a reference signal serving as a reference for forming the PWM control signal is controlled based on the differential time signal to a low value in accordance with the differential time.02-05-2009
20110304309SWITCHING POWER SOURCE APPARATUS - A switching power source apparatus includes a high-side MOSFET 12-15-2011
20110043181Single-inductor-multiple-output regulator with auto-hopping control and the method of use - A switching regulator is provided herein comprising a voltage source, a plurality of switching elements, an inductive element, and a controller. The controller coordinates the plurality of switching elements as to sequentially and periodically switching the inductive element to generate a plurality of regulated DC voltages. The controller adjusts a switching frequency of the regulator in accordance with at least one characteristic of a load current.02-24-2011
20100123446Feed-Forward Compensation for a Hysteretic Switching Regulator - One embodiment of the invention includes a hysteretic power regulator system. The system includes a switching stage configured to periodically couple an input voltage to an inductor in response to a control signal to generate an output voltage. The system also includes a hysteretic control stage configured to generate the control signal based on a comparison of a feedback voltage associated with the output voltage and a predetermined reference voltage. The system also includes a feed-forward stage configured to generate a feed-forward ramp voltage in response to the control signal. The feed-forward ramp voltage can be added to the feedback voltage to set a frequency of the control signal. The system further includes a compensation stage configured to cancel a DC error associated with the feed-forward ramp voltage relative to the feedback voltage to substantially mitigate errors associated with the output voltage.05-20-2010
20110304308Adaptive constant on time adjustment circuit and mathod for adaptively adjusting constant on time - The present invention discloses an adaptive constant ON time adjustment circuit, which generates a square wave signal having a constant normal ON time during normal operation, for controlling a power stage circuit to convert an input voltage to an output voltage. When the output voltage is shifted from low to high, during the transient period, the ON time is adjusted longer; and when the output voltage is shifted from high to low, during the transient period, the ON time is adjusted shorter.12-15-2011
20100001707STEPWISE RAMP VOLTAGE GENERATOR - A stepwise voltage ramp generator includes a tank capacitor, a terminal of which is coupled to a reference potential to be charged with a voltage ramp. A transistor couples the tank capacitor to a supply line. A diode-connected transistor, biased with a bias current is coupled to the transistor to form a current mirror. A by-pass switch is electrically coupled in parallel to the diode-connected transistor, and is controlled by a PWM timing signal, the duty-cycle of which determines a mean slope of the generated voltage ramp.01-07-2010
20110068763DUTY FEED FORWARD METHOD AND APPARATUS FOR MODULATING A DUTY OF A PMW SIGNAL AND POWER CONVERTING METHOD AND POWER CONVERTER USING THE SAME - The duty of a PWM signal in a power converter is extracted to feed forward to modulate the slope of a linear oscillating ramp signal or the voltage level of an error signal, so as to modulate the duty of the PWM signal, by which the transient response of the power converter and the stability of the PWM loop both are improved.03-24-2011
20100164462DC-DC CONVERTER PROVIDING SOFT-START FUNCTIONS - A DC-DC converter includes a switch circuit, a feedback circuit, an error amplifier, a soft-start circuit, and a signal modulation circuit. The switch circuit receives an input voltage and charges/discharges an inductor based on a switch control signal, thereby providing an output voltage. The feedback circuit provides a corresponding feedback voltage based on the output voltage. The error amplifier generates a comparing voltage based on the feedback voltage and a reference voltage. The soft-start circuit provides a ramp clamping voltage, which is outputted as the comparing voltage when the comparing voltage is larger than the ramp clamping voltage. The signal modulation circuit generates the switch control signal based on the comparing signal and a periodic signal.07-01-2010
20100277152CHARGE PUMP CIRCUIT AND METHODS OF OPERATION THEREOF - A method of generating a voltage supply (Vout+, Vout−) from a single input supply (+V11-04-2010
20120206121SYSTEM AND METHOD FOR SOFT-STARTING A POWER CONVERTER WITH A PRE-CHARGED OUTPUT - A method for soft-starting a voltage generator includes disabling an output driver; detecting the voltage on an output node; ramping a reference voltage at a controlled rate from a predetermined first level until the reference voltage reaches a second level that is a predetermined function of said output node voltage; enabling the output driver when the reference voltage reaches said second level; and then ramping the reference voltage and the output node voltage at a controlled rate to a boot voltage level. A soft-start circuit for an output voltage generator includes a comparator for causing a ramp generator to ramp the reference voltage and the voltage on the output node to a boot voltage level at a controlled rate once the comparator detects that the reference voltage is substantially equal to the voltage on the output node.08-16-2012
20120153922CONTROL FOR REGULATOR FAST TRANSIENT RESPONSE AND LOW EMI NOISE - Methods and circuits for power supply arrangement and control are disclosed herein. In one embodiment, a switching regulator can include: (i) a filter network coupled to an output terminal, where an output voltage is generated at the output terminal from an input source; (ii) an active switch to connect the input source to the filter network by periodically operating between on and off states over a switching period, where a duty cycle of the on state relative to the switching period is modulated based on a PWM control signal; (iii) a comparator receiving an output feedback signal, a hysteresis signal, and a reference level, and providing the PWM control signal therefrom; and (iv) a hysteresis programming circuit generating the hysteresis signal, and a ramp control signal, where the hysteresis signal is programmed based on conditions at the input source and the output voltage to achieve a pseudo constant frequency operation.06-21-2012
20120153921METHODS AND APPARATUSES FOR COMBINATIONS OF CURRENT FEEDBACK FOR FREQUENCY COMPENSATION, OVERLOAD DETECTION, AND SUPER OVERLOAD DETECTION IN SWITCHING POWER CONVERSION - A single replica current is proportional to current through a main switch of a switching power converter. This replica current may be used for current compensation, detection and response to an overload, detection and response to a super-overload, and combinations thereof. An input voltage is switchably coupled to an output signal generating a load current responsive to a switch control. A replica switch generates a replica current proportional to the load current. A ramp modulation signal may be generated. A voltage ramp of the ramp modulation signal may be adjusted in response to the replica current. A feedback difference signal is compared to the ramp modulation signal to generate a comparison output. Comparison of an overload reference voltage to a replica voltage proportional to the replica current generates an overload signal. The switch control is generated responsive to the comparison output and may be modified responsive to the overload signal.06-21-2012
20120249106STABILITY METHODS AND STRUCTURES FOR CURRENT-MODE DC-DC VOLTAGE CONVERTERS - DC-DC voltage converter structures and methods are provided that employ first and second transistors which are switched to control currents through an inductor and a capacitor to thereby provide an output voltage substantially equal to a predetermined reference voltage. Preferably included is a voltage feedback loop in which an error voltage is fed back to a loop comparator and further included is a current feedback loop that provides to the comparator a first voltage ramp whose amplitude is proportional to the amplitude of the converter's input current. The output signal of the comparator sets the duty cycles of the first and second transistors. In each converter period, the first and second transistors of the voltage converter respectively control, through the inductor, a first current with a rising slope and a second current with a falling slope. Finally, converter stability is enhanced by providing a second voltage ramp having a slope related to a fraction (e.g., ½) of the falling slope and then comparing the error voltage of the voltage feedback loop to the sum of the first and second voltage ramps.10-04-2012
20120126774SYSTEMS AND METHODS FOR SELF-RECYCLING POWER - A power system includes a switch, a capacitor and a comparator circuit. The power system receives a signal to turn off power supplied to the power system, turns off the switch that is used to supply power to the system and discharges the capacitor. The power system also compares a voltage across the discharging capacitor to a threshold voltage value, and turns on the switch to allow power to be supplied to the power system when the compared voltage across the discharging capacitor equals the threshold voltage value.05-24-2012
20110181265DC/DC CONVERTER CIRCUIT - A charging pump circuit of discharging electric charge charged during charging period to load during boosting period, and an amplifier and a voltage control resistor element arranged in feedback loop by being configured with the feedback loop of feeding back output voltage such that the output voltage of the charging pump circuit is made to be a predetermined value during boosting period are provided, the voltage control resistor element is controlled by the amplifier, and set to a control resistance value of enabling the charging pump circuit to control during boosting period, and the amplifier controls the voltage control resistor element such that the voltage control resistor element is brought into OFF state during charging period, and a resistance value of the voltage control resistor element is lowered to a control resistance value immediately after shifting from charging period to boosting period.07-28-2011
20110181264CONTROLLER FOR BUCK AND BOOST CONVERTER - A PWM controller for adjusting an output voltage of a buck and boost converter includes a first saw wave generator, which generates a first saw wave in accordance with the level of the output voltage. A first comparator coupled to the first saw wave generator compares the first saw wave with a first reference voltage and generates a first pulse. A peak hold circuit coupled to the first saw wave generator holds a peak value of the first saw wave. A second saw wave generator coupled to the peak hold circuit generates a second saw wave having a lower limit value that is the peak value of the first saw wave. A second comparator coupled to the second saw wave generator compares the second saw wave with the first reference voltage and generates a second pulse.07-28-2011
20090058388SWITCHING POWER SUPPLY DEVICE - This invention prevents undershoot, etc., occurring in the output during the transition from intermittent control mode to continuous control mode to hinder stability, responsiveness, and low power consumption.03-05-2009
20100052640Stability compensation circuit and DC-DC converter including the same - A stability compensation circuit and a DC-DC converter including the same are provided. When an output voltage of the DC-DC converter decreases more than a predetermined value, the stability compensation circuit quickly charges an integral capacitor by using an additional converter or by reducing an effective resistance of a charging circuit which charges the capacitor. Since an output voltage of an integrator in the stability compensation circuit is enabled to quickly reach a control voltage, the instant decrease of the output voltage of the DC-DC converter can be quickly compensated for.03-04-2010
20090066309SWITCHING REGULATOR - A switching regulator is disclosed that uses a non-linear amplifier and is capable of PWM control operation at high frequencies with a simple circuit configuration and without increasing current consumption. The switching regulator includes a switching unit, an inductor, a rectification unit, and a control circuit that controls the switching of the switching unit so that the output voltage of the switching regulator becomes a constant voltage. The control circuit uses a pulse signal to perform PWM control on the switching unit. The pulse signal is generated by amplifying an error voltage between the output voltage and a reference voltage at a gain variable in response to a voltage of a saw-tooth waveform signal.03-12-2009
20120229113SYSTEM AND METHOD FOR PREVENTING CONTROLLER INDUCED PULSE SKIPPING AT LOW DUTY CYCLE OPERATIONS - A voltage regulator generates a regulated output voltage responsive to an input voltage and drive control signals. An error amplifier generates an error voltage signal responsive to the regulated output voltage and a reference voltage. A PWM modulator generates a PWM control signal responsive to the error voltage signal, a ramp voltage and an inverse of the reference voltage. Control circuitry within the PWM modulator maintains the error voltage signal applied to the PWM modulator at substantially a same DC voltage level over the reference voltage operating range and maintains the error voltage signal above a minimum value of the ramp voltage. Driver circuitry generates the drive control signals responsive to the PWM control signal.09-13-2012
20120268096VOLTAGE BOOSTER SYSTEM AND SEMICONDUCTOR CHIP - A voltage booster system of a charge pump type includes a regulator for outputting a constant voltage and a charge pump circuit for boosting a voltage of an output terminal of the regulator. The regulator includes a differential amplifier unit for inputting a reference voltage and a feedback voltage according to the voltage of the output terminal, and an output stage portion including an PN connection element having one end portion connected to an application terminal of a power source voltage and another end portion connected to the output terminal. The PN connection element is configured to be controlled according to an output signal of the differential amplifier unit. The charge pump circuit includes a first capacitor to which the voltage of the output terminal is applied to be charged; a second capacitor; a third capacitor; a first switching section; and a second switching section.10-25-2012
20080252281Switching power supply circuit having soft start circuit - An exemplary switching power supply circuit includes at least a power input terminal, a power control chip, and a soft start circuit. The power input terminal is configured for receiving an operating voltage applied to the switching power supply circuit, and the power control chip is configured for modulating a pulse width of an output current of an optical coupler in the soft start circuit to gain a pulse width voltage of the switching power supply circuit. The soft start circuit includes a first resistor, a second resistor, a capacitor, and a transistor performing an amplifying function.10-16-2008
20080238397Circuit and method for soft start of a switching regulator from a residual voltage - For soft start of a switching regulator, the output voltage of the switching regulator is fed back to be compared with a ramp signal, in order to trigger a comparison signal when the ramp signal rises up to reach the feedback signal, to enable the switching regulator such that the output voltage changes from a residual voltage toward a target value. The low side switch of the switching regulator is kept off for a period of time after the switching regulator is enabled, so as to prevent a reverse current during the soft start period.10-02-2008
20080224681Controller for a DC to DC Converter - A controller for a DC to DC converter. The controller may include a resistor coupled to a switching node of the DC to DC converter. The switching node may be coupled to a high side switch and a low side switch of the DC to DC converter. A current level through the resistor may be responsive to a state of the high side switch and said low side switch. The controller may further include ramp generation circuitry responsive to the current level through the resistor to provide a ramp signal, and pulse width modulation (PWM) circuitry configured to generate a PWM signal in response to at least the ramp signal.09-18-2008
20110273156POWER REGULATOR, CONTROL CIRCUIT, AND METHOD FOR CONTROLLING POWER REGULATOR - A power regulator includes an output terminal, which outputs an output voltage, and a converter unit including a switch circuit, which is supplied with an input voltage, and a coil, which is coupled between the switch circuit and the output terminal. A control circuit compares a feedback voltage, which is in accordance with the output voltage, and a reference voltage and controls the switch circuit in response to a switching timing that is in accordance with the comparison result. The control circuit includes a voltage adding circuit, which adds a ramp voltage to the feedback voltage or the reference voltage, and a timing adjustment circuit, which is coupled to the voltage adding circuit to delay a timing for adding the ramp voltage with the voltage adding circuit from a switching timing of the switch circuit.11-10-2011
20130147456DC-DC CONVERTER - A DC-DC converter including a Pulse Width Modulation (PWM) controller for converting an input voltage into an output voltage is provided. The PWM controller includes: an error amplifier, receiving a reference voltage and a feedback voltage and provides an error signal; a compensation unit coupled to an output of the error amplifier, compensating the error signal and comprising a first resister and a first capacitor; a ramp generator, generating a ramp signal according to a constant on time PWM signal; a first comparator coupled to the compensation unit and the ramp generator, comparing the compensated error signal with the ramp signal to generate a trigger signal; and a PWM generator coupled to the first comparator, providing the constant on time PWM signal according to the trigger signal, an input voltage of the DC-DC converter and the output voltage of the DC-DC converter.06-13-2013
20130200873Methods and Apparatuses for a Soft-Start Function with Auto-Disable - Methods and apparatuses for a soft-start function with auto-disable are described. Such methods and apparatuses can gradually increase a voltage towards a reference voltage using a ramp generator and a control loop and can disable the ramp generator and the control loop once the voltage has reached the reference voltage.08-08-2013
20130207632SYSTEM AND METHOD FOR IMPROVED LINE TRANSIENT RESPONSE IN CURRENT MODE BOOST CONVERTERS - An improved DC-DC power converter employs a feed-forward circuit to improve the response of the output voltage to transient signals on the input voltage. A portion of the input voltage generated by the feed-forward circuit is combined with either the sense voltage or the set point reference to offset one of the voltages applied to the PWM circuit comparator. The feed-forward circuit essentially bypasses the PWM feedback loop to quickly pre-compensate for the input transient and allow the output voltage to settle rapidly at a new operating point. The feed-forward circuit can be implemented with a resistive voltage divider network connected to the input voltage.08-15-2013
20130207633SWITCHING REGULATOR - Provided is a switching regulator including a circuit for detecting a short-circuit state easily and reliably, without the need of an adjustment step such as trimming. In accordance with a drive signal of a power switching element of the switching regulator, a discharge circuit is controlled. When the power switching element is short-circuited and becomes the ON state all the time, the discharge circuit stops its operation, and a capacitor is continuously charged. A voltage detection circuit detects that a charge voltage of the capacitor has reached a predetermined potential, to thereby detect the short-circuit state.08-15-2013

Patent applications in class With ramp generator or controlled capacitor charging