| Entries |
| Document | Title | Date |
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| 20130044525 | ASYMMETRIC SWITCHING RECTIFIER - An asymmetric switching rectifier includes a first switching device to allow electric current to flow while in a first state and inhibit electric current in a second state and a second switching device connected in a head-to-head formation to said first switching device, said second switching to allow electric current to flow while in a first state and inhibit electric current in a second state. A first electric current to turn said switching devices to said first state is different than a second electric current to turn said switching devices to said second state. The rectifier further includes a bypass segment to draw a bypass electric current from a center electrode between said first switching device and said second switching device. | 02-21-2013 |
| 20120163049 | APPARATUS FOR COLLECTING WIRELESS ENERGY AND WIRELESS ELECTRONIC LABEL EMPLOYING THE APPARATUS - An apparatus for collecting wireless is provided. The apparatus includes an antenna and a collection circuit. The antenna generates an alternating current (AC) voltage from a radio wave. The collection circuit generates a direct current (DC) voltage corresponding to the AC voltage, determines whether the DC voltage is lower than a preset value, and changes an internal impedance of the collection circuit if it is determined that the DC voltage is lower than the preset voltage. | 06-28-2012 |
| 20100073974 | DIGITAL PEAK INPUT VOLTAGE DETECTOR FOR A POWER CONVERTER CONTROLLER - An example integrated circuit controller for a power converter includes a digital peak detector and a switching block. The digital peak detector is coupled to output a digital count signal representative of a peak input voltage of the power converter. The switching block is coupled to control switching of a power switch of the power converter to regulate an output of the power converter. The switching block is further coupled to control the switching of the power switch in response to the digital count signal. | 03-25-2010 |
| 20130077364 | POWER CONVERTER AND THE METHOD THEREOF - The present disclosure discloses a power converter providing a low output voltage from an offline AC. The power converter defines a voltage window for the input AC signal. Inside the voltage window, the rectified DC waveform is passed through to the output and the storage capacitor; outside the voltage window, the power converter is idle (or the output is blocked from input) and let the output storage capacitor alone supply the load. | 03-28-2013 |
| 20120206947 | Load Detection for a Low Power Mode in an AC-DC Adapter - Various embodiments of the present invention relate to AC-DC adapters, and more particularly, to systems, devices and methods of employing a load detector to detect a load condition of the AC-DC adapters based on transient variation of a DC output voltage; and therefore, enable the AC-DC adapters to switch from a low power mode to a normal power mode. At the low power mode, a DC output voltage is generated at a target voltage by the AC-DC adapter, and subsequently drops at a decay rate dependent on load condition. The load detector is electrically coupled to monitor the output voltage and measure the decay time between two threshold voltages. An enable instruction is provided to configure the AC-DC adapter to the normal power mode as soon as the decay time is lower than the threshold decay time or the variation of consecutive decay times reaches a certain threshold. | 08-16-2012 |
| 20130070495 | AC/DC CONVERTER - The present invention relates to an AC/DC converter comprising at least two phase legs connected in series between first and second DC connection terminals of the AC/DC converter, wherein each phase leg comprises: an AC connection having first and second terminals arranged to connect the phase leg to a phase of an AC system; a phase branch comprising at least one converter cell and having first and second branch end terminals; and a capacitor. The capacitor is connected the between the first branch end terminal and the first AC connection terminal, so that the capacitor forms a DC blocking capacitor. The second AC terminal is connected to the second branch end terminal. The series connection of the phase legs between first and second DC connection terminal is such that a first series connection point in a phase leg is located between the first branch end terminal and the capacitor, while a second series connection point is located between the second branch end terminal and the second AC connection. The invention further relates to a method of operating such AC/DC converter. | 03-21-2013 |
| 20120218792 | DIGITAL PHASE ADJUSTMENT FOR MULTI-PHASE POWER CONVERTERS - A multiphase power converter includes one or both of a phase control circuit and a valley switching locking circuit. The phase control circuit measures a phase difference between a first phase circuit and a second phase circuit and varies an on-time of a drive switch of the second phase circuit to produce and maintain a predetermined phase difference between the first phase circuit and the second phase circuit. When the multiphase power converter is operating in a discontinuous mode of operation, the valley switching locking circuit counts the number of zero crossings of an input current of the first phase circuit and blocks a second zero crossing detection signal from a waveform generator (i.e., PWM driver) associated with the second phase circuit until an input current of the second phase circuit has as many zero crossings as that of the first phase circuit input current. | 08-30-2012 |
| 20090268493 | POWER-ON RESET CIRCUIT AND ELECTRONIC DEVICE USING THE SAME - A power-on reset circuit connected to an external DC power source includes a delay circuit, a rectifying circuit, and a logic operation circuit. The delay circuit includes a first delay unit used for outputting a first delaying reference signal and a second delay unit used for outputting a second delaying reference signal. The rectifying circuit connected to the delay circuit includes a first rectifying unit and a second rectifying unit. The first rectifying unit is connected to the first delay circuit used for rectifying the first delaying reference signal to output a first rectified signal. The second rectifying unit is connected to the second delay circuit used for rectifying the second delaying reference signal to output a second rectified signal. The logic operation circuit is connected to the rectifying circuit used for outputting a reset signal according to the first rectified signal and the second rectified signal. | 10-29-2009 |
| 20090268492 | Switching Regulator and Electronic Device Therewith - A switching regulator ( | 10-29-2009 |
| 20120224401 | Variable Input Voltage PFC Circuits, Systems and Power Supplies With Phase Shifted Power Rails - A method of generating an output voltage from a variable input voltage with a power factor correction (PFC) system is disclosed. The PFC system includes a first power rail and a second power rail connected in parallel between an input for receiving the input voltage and an output for outputting the output voltage. The method includes operating one or both of the first power rail and the second power rail to generate the output based, at least in part, on whether the input voltage exceeds a threshold voltage. Power supplies and PFC systems suitable for performing the method are also disclosed. | 09-06-2012 |
| 20130121047 | ACTIVE POWER FACTOR CORRECTION CIRCUIT AND RELATED PFC CONTROLLER - An active power factor correction (PFC) circuit for calibrating a power factor of an AC-to-DC converter when the active PFC circuit is coupled with the AC-to-DC converter is disclosed including: a piecewise linear gain circuit, an error amplifier, a PWM controller, and a PWM signal generator. The piecewise linear gain circuit is for receiving a feed forward signal and generating a corresponding gain signal, wherein the gain signal and the feed forward signal have a broken line relation with respect to magnitude. The error amplifier is for generating an error signal according to an output voltage of the AC-to-DC converter. The PWM controller is for generating a control signal according to the gain signal and the error signal. The PWM signal generator is for generating a PWM signal for controlling a power switch of the AC-to-DC converter according to the control signal. | 05-16-2013 |
| 20090027931 | AC-DC CONVERTER - An AC-DC converter includes a rectifier DB for rectifying an alternating current supplied from an alternating power source AC, a power factor controller | 01-29-2009 |
| 20130128637 | POWER RAIL REGULATOR SYSTEM - A power regulators system and method is disclosed. In one embodiment, a power regulator system ( | 05-23-2013 |
| 20110280052 | MULTILEVEL ELECTRIC POWER CONVERTER - There is described a multilevel electric power converter circuit comprising: N | 11-17-2011 |
| 20100124083 | 3-PHASE POWER FACTOR CORRECTED AC TO DC FILTERED SWITCHING POWER SUPPLY - This invention relates to a power supply apparatus and method for converting three-phase delta AC power to DC power using EMI filters and PFC circuits to maintain balanced AC current loading and reduce radiated and conducted emissions. Overcurrent and temperature protection are also provided in conjunction with a novel optocoupler latch circuit for improving maintenance of the power supply. | 05-20-2010 |
| 20110292699 | Systems and Methods for Distortion Reduction - Systems and devices for reduction of total harmonic distortion in power supply circuits are presented. Example embodiments of the disclosed systems of total harmonic distortion reduction reduce a low frequency output voltage ripple seen by the voltage control loop by adding a compensating ripple voltage to the output feedback signal. The compensating signal may be scaled by the user to optimize the degree of ripple reduction, and may be automatically adjusted by monitoring circuitry to scale with a power factor control circuit output power level. | 12-01-2011 |
| 20090279332 | Flyback constant voltage converter having both a PWFM mode and a PWM mode - A flyback AC/DC switching converter has a constant voltage (CV) mode. The CV mode has sub-modes. In one sub-mode (“mid output power sub-mode”), the output voltage (VOUT) of the converter is regulated using both pulse width modulation and pulse frequency modulation. Both types of modulation are used simultaneously. In a second sub-mode (“low output power sub-mode”), VOUT is regulated using pulse width modulation, but the converter switching frequency is fixed at a first frequency. By setting the first frequency at a frequency above the frequency limit of human hearing, an undesirable audible transformer humming that might otherwise occur is avoided. In some embodiments, the converter has a third sub-mode (“high output power sub-mode”), in which pulse width modulation is used but the switching frequency is fixed at a second frequency. By proper setting of the second frequency, undesirable EMI radiation and other problems that might otherwise occur are avoided. | 11-12-2009 |
| 20110267856 | PFC WITH HIGH EFFICIENCY AT LOW LOAD - A Power Factor Corrector (PFC), typically used as the first stage of switched mode power supplies, particularly suited for Universal Mains inputs, is disclosed, along with methods for controlling a switched mode power supply having power factor correction. In order to increase efficiency, particularly under low load conditions, without undue degradation of the Power Factor, the switching of the PFC circuit is confined to one or more operating windows within each half-cycle. In embodiments, the operating window comprises a small time window centred around the peak of the mains voltage. The higher the power level, the wider the switching window. | 11-03-2011 |
| 20130010508 | MAIN SUPPLY ZERO CROSSING DETECTION FOR PFC CONVERTER - A fault mode of a PWM module embedded in a microcontroller is used to detect main supply zero crossings for regulating output voltage of a PFC converter operating in BCM, without using an external detecting element or a comparator, ADC or other specialized component internal to the microcontroller. In some implementations, the end of decrease current flow in the energy storage inductor of the converter is used to reinitialize a PWM timer or counter (counting-up or counting-down timer). The current goes to zero for a time period when the main supply voltage goes to zero, resulting in the PWM timer or counter not being reinitialized prior to the end of the current PWM cycle. The failure to reinitialize the timer or counter can be used to generate a signal indicative of a zero voltage crossing of the main supply voltage. | 01-10-2013 |
| 20120106213 | THREE-PHASE RECTIFIER - A three-phase rectifier converts three-phase alternating current (AC) power supplied from a three-phase AC power supply into direct current (DC) power. The three-phase rectifier includes a full-wave rectifier circuit, a bidirectional switch circuit, and a controller. The full-wave rectifier circuit rectifies three-phase AC power to DC power. The bidirectional switch circuit switches on and off inputs of respective phases from the three-phase AC power supply to the full-wave rectifier circuit. The controller detects voltages of the respective phases of the three-phase AC power supply, generates switching patterns for the respective phases to switch the bidirectional switch circuit on and off based on the detected voltages of the phases, and controls switching of the bidirectional switch circuit based on the switching patterns. | 05-03-2012 |
| 20090262562 | EFFICIENCY IMPROVEMENT IN POWER FACTOR CORRECTION - An power converter that is operable to convert AC power into DC power that may be delivered to a load. The power converter includes a transformer and a controllable switch. The switching frequency of the power converter is configured to be dependent on the level of the AC voltage of an AC power source. The switching frequency may be proportional to the AC voltage to provide a constant magnetic flux density swing for the transformer in the power converter. The switching frequency may be controlled by using a circuit that converts the AC voltage from the AC power source into a frequency signal that is proportional to the AC voltage. | 10-22-2009 |
| 20090279331 | Acdc converter - This invention relates to an ACDC converter ( | 11-12-2009 |
| 20090168475 | CONVERTER POWER SUPPLY CIRCUIT AND CONVERTER POWER SUPPLY DRIVING METHOD - A converter power supply circuit | 07-02-2009 |
| 20080247203 | Energy Efficient Power Converter - There is disclosed a power supply and method. The power supply may include a power converter for converting AC primary power into DC power, the power converter having a normal operating mode and a low power quiescent operating mode. A DC power plug may be adapted to deliver DC power from the power converter to a load. The normal operating mode and the low power quiescent operating mode of the power converter may be selected by a switch integrated into the DC power plug. | 10-09-2008 |
| 20090097288 | OUTPUT POWER SWITCHING VECTOR SCALING SYSTEM AND METHOD - A power converter control system and method is provided to maximize the power output of the converter where an overload condition is present. A controller calculates a command voltage and command power factor. The command voltage and command power factor are used to generate a switching vector. Where the voltage associated with a switching vector exceeds an output voltage limit of the converter, a power factor adjustment is generated. | 04-16-2009 |
| 20090097289 | FEEDBACK COMMUNICATION TECHNIQUE FOR SWITCHED MODE POWER SUPPLY - A power conversion circuit for a switched mode power supply (SMPS) | 04-16-2009 |
| 20120063183 | POWER SUPPLY INPUT DEVICE - A power supply input device including a first resistance of a discharge resistance conversion unit connected in parallel to a discharge resistance unit; and a switching unit of the discharge resistance conversion unit connected to the first resistance and performing a switching operation according to an externally received control signal, thus minimizing power losses occurring when a system is in a standby mode. | 03-15-2012 |
| 20090027930 | AC-DC CONVERTER - An AC-DC converter includes a rectifier DB for rectifying an alternating current supplied from an alternating power source AC, a power factor controller | 01-29-2009 |
| 20090116269 | Power supply with reduced power consumption when a load is disconnected from the power supply - Detection and control circuitry are added to a conventional power supply to detect when a load, such as a portable electronic device, has been disconnected from the power supply and, when disconnected, interrupt a current path to the primary windings of a transformer within the power supply to substantially reduce the amount of reactive power that is consumed by the power supply. | 05-07-2009 |
| 20110235378 | POWER SUPPLY SYSTEM FOR ELECTRONIC DEVICE - A power supply system includes an AC power source, a converter, a relay switch, and a waveform monitoring circuit. The AC power source provides an AC voltage. The converter is capable of converting the AC voltage into a DC voltage. The relay switch is connected between the AC power source and the converter. The waveform monitoring circuit is connected to the AC power source, and monitors a waveform of the AC voltage provided by the AC power source. The waveform monitoring circuit is connected to the relay switch, and turns on the relay switch when an absolute value of an instantaneous voltage of the AC voltage is not bigger than a threshold voltage. | 09-29-2011 |
| 20090129130 | POWER CONVERTER - This invention relates to a power converter ( | 05-21-2009 |
| 20090154206 | Circuit and associated method for reducing power consumption in an a power transformer - A method and circuit is provided for reducing power consumption in a power transformer, typically incorporated into an electrical or electronic device such as a consumer device. In an embodiment, a detection/isolation circuit is coupled to an input of a power transformer/rectifier via a switching device. The switching device can be, for example, a solid state relay. The detection/isolation circuit is configured to sense the occurrence of no-load conditions in the power transformer and responsively disengage the power transformer from a coupled source of power (e.g., wall outlet) via the coupled switching device. | 06-18-2009 |
| 20110051477 | Front-end circuit of power converter - A front-end circuit of a power converter has a power connection wiring detecting circuit, a power switch and a control unit. The power connection wiring detecting circuit is connected to an AC power. The control unit is connected to the power connection wiring detecting circuit. The power switch is connected to the power loop. The control unit turns on or off the AC power loop through the power switch. When the power connection wiring is correctly connected with the AC power, the control unit turns on the power switch and the front-end circuit outputs the AC power to the back-end circuit. When the power connection wiring is incorrectly connected with the AC power, the control unit turns off the power switch and the AC power is not outputted to the back-end circuit. | 03-03-2011 |
| 20100265743 | CONTACT-INPUT ARRANGEMENT FOR POWER SYSTEM DEVICES - A contact-input circuit for a power system device is described for processing a higher voltage signal from power system equipment or another power system device for use by a lower voltage circuit. The contact-input circuit generally includes a voltage threshold detection device adapted to allow current to flow therefrom when it detects that the higher voltage signal reaches a select threshold. An opto-isolator device, which is coupled to the voltage threshold detection device, provides a voltage signal suitable for use by the lower voltage circuit when the threshold detection device allows the current-flow through the opto-isolator. | 10-21-2010 |
| 20120201062 | STANDBY POWER CUT-OFF DEVICE AND CONTROL METHOD THEREOF AND POWER SUPPLY - The present invention is related to a standby power cut-off device that cuts off standby power generated from an electrical appliance by learning power on/off control data sent from a remote control, and upon receipt of the power on/off control data of the remote control, simultaneously controls commercial power (main power) supplied to the electrical appliance, and a control method thereof. | 08-09-2012 |
| 20080205103 | POWER FACTOR CONTROL SYSTEMS AND METHODS - A boost converter comprises an inductance that receives an input signal. A switch controls current supplied via the inductance to a load. A power factor control module comprises a mode control module that selects an operating mode of the boost converter and a switch control module that switches the switch at a frequency. The frequency is equal to a first frequency when the mode control module selects a continuous mode and equal to a second frequency when the mode control module selects a discontinuous mode. The first frequency is greater than the second frequency. | 08-28-2008 |
| 20080205102 | Power Supply - A power supply (V | 08-28-2008 |
| 20100195358 | VOLTAGE REGULATOR AND AC-DC CONVERTER - A voltage regulator is provided. An input node receives an input voltage. An output node provides a supply voltage. A first transistor is coupled between the input node and a node. A first resistor is coupled between the input node and a gate of the first transistor. A second transistor is coupled between the node and the output node. An amplifier includes a non-inverting input terminal for receiving a reference voltage and an inverting input terminal. A second resistor is coupled between the inverting input terminal and a ground. A third transistor is coupled between the second resistor and a gate of the second transistor, wherein the third transistor is controlled by an output of the amplifier. A fourth transistor is coupled between the third transistor and the first node, wherein a gate of the fourth transistor is coupled to the gate of the second transistor. | 08-05-2010 |
| 20120099354 | CIRCUITS AND METHODS FOR ALTERNATING CURRENT-TO-DIRECT CURRENT CONVERSION - An AC-to-DC converter for converting an AC voltage to a DC voltage includes a first converter, a second converter, a sense circuit, a controller, and an enabling circuit. The first converter converts an AC voltage to a first DC voltage. The second converter converts the first DC voltage to a second DC voltage. The sense circuit coupled to the first and second converters provides a first sense signal indicative of the first DC voltage and a second sense signal indicative of the AC voltage. The controller coupled to the first and second converters controls the first and second DC voltages. The enabling circuit coupled to the sense circuit generates a control signal to the controller to disable both the first converter and the second converter by comparing the first sense signal to a first threshold voltage and comparing the second sense signal to a second threshold voltage. | 04-26-2012 |
| 20110317458 | SWITCHED-MODE POWER SUPPLY CONTROLLING CIRCUIT AND SWITCHED-MODE POWER SUPPLY USING THE SAME - A controlling circuit is provided for controlling an output voltage of a main circuit of a switched-mode power supply. The controlling circuit includes components that generate a switching status selecting signal reflecting a voltage change of the main circuit, and output a reference voltage according to a voltage output status selected according to the switching status selecting signal. Other components output a pulse width modulation controlling signal according to the reference voltage and a current signal reflecting a current change of the main circuit, and output a pulse frequency modulation controlling signal with a frequency according to a frequency output status selected according to the switching status selecting signal. Yet other components output a switching controlling signal according to the controlling signals, and control a switch of the main circuit to switch-on or switch off according to the switching controlling signal to stabilize the output voltage of the main circuit. | 12-29-2011 |
| 20120155133 | DIRECT CURRENT/ DIRECT CURRENT CONVERTER FOR REDUCING SWITCHING LOSS, WIRELESS POWER RECEIVER INCLUDING DIRECT CURRENT/ DIRECT CURRENT CONVERTER - Provided are a direct current/direct current (DC/DC) converter and a wireless power receiver including the DC/DC converter. In one embodiment, a direct current-direct current (DC/DC) converter for use in a wireless power receiver, the DC/DC converter may include: a voltage converting unit configured to convert, DC voltage, to a predetermined DC voltage; a turn-on switch configured to control current flow of the DC voltage through the voltage converting unit; and a switching controller configured to: detect an amount of current of the voltage converting unit based on a first turn-on period of the turn-on switch, set a second turn-on period of the turn-on switch based on the detected amount of current, and control the turn-on switch based on the second turn-on period. | 06-21-2012 |
| 20090091958 | DEVICE FOR SIMULATING RECTIFIED CONSTANT IMPEDANCE LOAD AND METHOD THEREOF - The device for simulating a rectified constant impedance load provide by the present invention is to test a power product and comprises an analog-digital converter, a digital signal processor, a digital-analog converter, and an active electrical load module in order to replacing the passive components of a traditional rectified passive load. method for simulating a rectified constant impedance load being applied to test a power product and comprising the steps of: (S1) replacing the plurality of passive components of the rectified constant impedance load with a digital control module and an active electrical load module; (S2) establishing a passive load model function in order to represent the application relationships of the plurality of the passive components; (S3) executing the operation of the passive load model function by the digital control module in order to gain a load current value, and transferring the load current value to an analog control signal via the digital control module; and (S4) controlling the active electrical load module via the analog control signal so as to draw currents from the power product. | 04-09-2009 |
| 20120014149 | POWER CONVERSION APPARATUS AND METHOD - According to one embodiment a power conversion apparatus includes a first switch, a second switch, and a pulse generator. The first switch is connected at both ends of an AC power supply through an inductor and capacitor connected in series. The second switch is connected at both ends of the first switch through a smoothing capacitor connected in series. The pulse generator generates a first pulse signal for driving the first switch at a frequency higher than a cycle of the AC voltage, and supplies it to the first switch, when the polarity of the voltage of the AC power supply is positive. The pulse generator generates a second pulse signal for driving the second switch at a frequency higher than a cycle of the AC voltage, and supplies it to the second switch, when the polarity of the voltage of the AC power supply is negative. | 01-19-2012 |
| 20120155134 | HIGH EFFICIENCY RECTIFIER, WIRELESS POWER RECEIVER INCLUDING THE RECTIFIER - A high efficiency rectifier and a wireless power receiver including the rectifier are provided. In one embodiment, a rectifier may be formed of a full bridge diode circuit and may include: a first dual diode, a second dual diode, a third dual diode and a fourth dual diode forming the full bridge diode circuit, the full bridge diode circuit including: a first path configured to output voltage when the phase of an input voltage is positive, via the first dual diode and the fourth dual diode; and a second path configured to output voltage when the phase of the input voltage is negative, via the second dual diode and the third dual diode. In another embodiment, a rectifier may include: at least two full bridge diode circuits connected in parallel. | 06-21-2012 |
| 20120026766 | CONTROL DEVICE OF A SWITCHING POWER SUPPLY - A control device controls a switching converter that converts an alternating supply voltage to a regulated voltage and comprises a switch connected to an inductor. The control device is adapted to control the on period and the off period of said switch for each cycle. The control device comprises a ramp generator adapted to generate a ramp voltage, a comparator adapted to determine the final instant of the on period of the switch by crossing the ramp voltage with a first voltage. The control device has a first signal representing a current through the inductor and a second signal representative of the current flowing through at least one element of the converter. The control device is adapted to control the closing of said switch according to said first signal and comprises a synchronizer adapted to synchronize the start of the ramp voltage with the zero crossing of said second signal. | 02-02-2012 |
| 20120300517 | POWER FACTOR CORRECTOR WITH HIGH POWER FACTOR AT LOW LOAD OR HIGH MAINS VOLTAGE CONDITIONS - A power factor corrector raises power factor at low loads or high mains voltages by modifying the switch timing or the current received by the power converter. It achieves this by increasing the switch-on time of a control switch during the falling time so that the majority of the switch-on time during a mains period occurs during the falling time, to thereby control the current received by the converter to compensate for current received by the intermediate filter. Some embodiments may employ a feedback system to produce one or more error signals that modify the control signal used to control the operation of the converter. Various embodiments may also include additional stages that limit the compensation range of the error signal. | 11-29-2012 |
| 20100091531 | METHODS AND SYSTEMS FOR REDUCING POWER CONSUMPTION - Methods and systems for managing power are described. In one embodiment of a method, a DC input voltage from an AC mains to DC converter, inputted to a DC to DC converter, is adjusted lower while maintaining substantially constant DC output voltage from the DC to DC converter in order to improve power efficiency. | 04-15-2010 |
| 20100246222 | METHOD AND APPARATUS FOR DIGITAL CONTROL OF A SWITCHING REGULATOR - Various techniques directed to the digital control of a switching regulator are disclosed. In one aspect, a power supply regulator includes a compare circuit to be coupled to receive a feedback signal representative of an output level of a power supply. This causes a feedback state signal to be generated having a first feedback state that represents an output level of the power supply that is above a threshold level and a second feedback state that represents an output level of the power supply that is below the threshold level. An adjustment circuit is coupled to the compare circuit to adjust the feedback state signal in response to at least one of adjusting the threshold level or adjusting the feedback signal. The adjustment to the feedback state signal tends to cause the feedback state signal to revert from a state at the time of adjustment to a state immediately preceding the adjustment. A control circuit is to be coupled to a power switch and is to be coupled to receive an oscillating signal and the feedback state signal. The control circuit is to control switching of the power switch in response to the oscillating signal and the feedback state signal to regulate the output level of the power supply. | 09-30-2010 |
| 20120257427 | ACTIVE RECTIFICATION OUTPUT CAPACITORS BALANCING ALGORITHM - An active rectification system includes an active rectifier that converts an alternating current (AC) input to a direct current (DC) output. The active rectifier includes a plurality of switching devices and at least a first output capacitor and a second output capacitor connected at the DC output of the active rectifier. A controller includes a DC output regulation portion and an output capacitor balancing portion, wherein the DC output regulation portion monitors the DC output and in response generates control signals for regulating the DC output to a desired value. The output capacitor balancing portion monitors first and second output capacitor voltages associated with the first and second output capacitors, respectively, and generates an accumulated adjustment value that modifies the control signals provided by the DC output regulation portion to balance the first and second output capacitor voltages. | 10-11-2012 |
| 20120262961 | Low cost high power factor LED driver - A controller for a power supply having a primary side and a secondary side includes a mapping circuit for generating a feedback signal corresponding to an output current of the secondary side, a power switch coupled to the primary side for conducting a connection according to a modulation signal, a constant current block, for generating a first current signal according to the feedback signal; and a control unit, for generating the modulation signal to control the power switch according to the first current signal. | 10-18-2012 |
| 20110038189 | CLOSED-LOOP EFFICIENCY MODULATION FOR USE IN AC POWERED APPLICATIONS - A system and method for closed-loop efficiency modulation for an AC/DC power system is provided. A boost-buck converter and a DC/DC converter connected in series receive a rectified DC feed signal from a AC input signal and deliver a modified DC output to an active load. A controller receives power data at various stages of the system and uses that data to modify a series of trim voltages provided to the feedback inputs of the respective converters to modify each converters output voltage. The controller modifies each converter's output voltage to maximize power efficiency while monitoring other data in the system to ensure the system is operating correctly and safely. | 02-17-2011 |
| 20120275203 | AC-DC CONVERTER AND METHOD OF CONTROLLING SAME - To provide an AC-DC converter that is highly efficient in a broad load current range from a light load to a heavy load. | 11-01-2012 |
| 20080298101 | INTELLIGENT DEAD TIME CONTROL - A circuit for reducing switching losses in a synchronous rectifier of a switching stage including a high-side control transistor and a low-side synchronous transistor coupled at a switching node, the switching stage receiving an input voltage and providing a controlled output voltage at an output node. The circuit including a first circuit portion for sensing waveshape edges of a first signal at a gate terminal of the low-side synchronous transistor and a first voltage to determine a delay between the waveshape edge of the first signal and the waveshape edge of the first voltage; and a second circuit portion for calibrating the first signal and the first voltage to align the waveshape edge of the first signal and the waveshape edge of the first voltage, with an optional offset to achieve minimal power loss. | 12-04-2008 |
| 20120092910 | SWITCHING POWER SUPPLY APPARATUS - A switching power supply is provided to supply an AC input voltage. The supply includes a control circuit configured to detect a voltage of the AC power source in a voltage waveform, and switch elements in a synchronous rectification switching mode in synchronization with polarities of the voltage waveform when the AC input voltage is equal to or greater than a predetermined voltage value. The control unit also operates the switching without synchronization with the polarities when the AC input voltage is smaller than the predetermined voltage value. | 04-19-2012 |
