Abstract: A full bridge phase shifted power supply with synchronous rectification and current doubler and method for dynamically adjusting delay parameters thereof mainly have multiple delay parameter combinations respectively varying with multiple loads and embedded in a controller of the power supply. The delay parameter combinations serve to determine driving waveforms of two rectification switches of a synchronous rectification and current doubler circuit of the power supply. When the load of the power supply varies, the controller dynamically performs a corresponding delay parameter combination so as to vary the driving waveforms of the rectification switches of the synchronous rectification and current doubler circuit and enhance the operating efficiency of the power supply.

Abstract: The present invention relates to a switch control circuit, a switch control method, and a converter using the same. An input voltage rectified from an AC input in a converter is transmitted to an inductor, and output power is generated from an inductor current by the input voltage. The converter includes a power switch connected to the inductor to control the inductor current and a sense resistor having a first end connected to a ground and a second end connected to the AC input. At a time point that a sense voltage generated in the sense voltage reaches the peak point and then decreased to an on-reference voltage, the power switch is turned on. The on-reference voltage is a sense voltage at a resonance start time point between a parasite capacitor of the power switch and the inductor.

Abstract: A switch mode power supply (SMPS) is capable of reducing standby power consumption, and includes a power factor capacitor (PFC) bulk capacitor which supplies power in a standby mode to constant loads by repeatedly charging and discharging a voltage, a PFC controller which controls the voltage to be charged in the PFC bulk capacitor, a first resistor and a second resistor which divide the voltage of the PFC bulk capacitor and output a reference voltage, and a control unit which controls the charging and discharging of the voltage of the PFC bulk capacitor in accordance with the reference voltage.

Abstract: In one aspect of the present invention, a battery charging system has a first rectifier adapted for converting an AC voltage at an input thereof to a first DC voltage at an output thereof; a power factor correction (PFC) circuit coupled to the first rectifier, for correcting the power factor of the battery charging system and outputting a second DC voltage; a first power converter coupled to the PFC circuit, for converting the second DC voltage to a third DC voltage; a second power converter coupled to the first power converter, for converting the third DC voltage to a fourth DC voltage to be delivered to a battery; and a first controller adapted for sensing the fourth DC voltage at the output of the second power converter for regulating the second power converter to maintain the fourth DC voltage at a predetermined value.

Abstract: A converter includes a rectifying circuit of an AC voltage of an AC power source into a rectified voltage, an input smoothing capacitor Ci, a first series circuit connected to the input smoothing capacitor and including a first and a second switching elements, a second series circuit connected to a connection point of the first and second switching elements and a first end of the input smoothing capacitor and including a primary winding of a transformer and a first capacitor Cri, a controller to alternately turn on/off the first and second switching elements, a rectifying-smoothing circuit (D1, Co) to rectify and smooth a high-frequency voltage of a secondary winding of the transformer into a DC output voltage, and a second capacitor connected between a connection point of the primary winding of the transformer and the first capacitor and a first end of the AC power source.

Abstract: A converter circuit including a step-up converter including a rectifier, a step-up reactor, a switching element, and a reverse current prevention element; a step-up converter having a step-up reactor, a switching element, and a reverse current prevention element and connected in parallel with the step-up converter; a switching control unit that controls switching elements; and a smoothing capacitor that is provided at the output of the step-up converters. The switching control unit switches the current mode of the current flowing through the step-up reactors into any of a continuous mode, a critical mode, and a discontinuous mode based on a predetermined condition.

Abstract: A converter control device comprises: a voltage-zero-cross detection unit detecting zero cross of the alternate-current voltage and outputting a voltage zero-cross signal; a power-source-current detection unit detecting a power source current of the alternate-current power source; a bus-line-voltage detection unit detecting a bus-line voltage between terminals of the smoothing capacitor; a PWM-signal generation unit generating a PWM-signal for on/off-controlling the switching unit, based on the power-source current, the bus-line voltage and a bus-line-voltage command value as a target voltage of the bus-line voltage; a power-source voltage-state detection unit detecting a signal state of the alternate-current voltage based on the voltage zero-cross signal; and a fundamental-switching-frequency selection unit selecting a fundamental switching frequency of the PWM-signal based on the signal state of the alternate-current voltage.

Abstract: A mode controller shifts, along with increase in an electric power in first and second of chopper circuits and, operation modes of the first and the second of the chopper circuits from a first mode to a third mode via a second mode. An operation controller causes, in the first mode, the first of chopper circuit to perform an chopping operation, and the second of chopper circuit to suspend the chopping operation, in the second mode, causes the first and the second of chopper circuits to alternatively perform the chopping operations, and in the third mode causes both of the first and the second of chopper circuits to perform the chopping operations.

Abstract: An active rectification system includes an active rectifier, a pulse width modulation (PWM) control, and a closed loop vector control. The PWM control portion is configured to control switching of the active rectifier and the closed loop vector control is configured to generate the required duty cycles for the PWM signals that regulate the DC voltage output and force a three-phase current input of the active rectifier to align with a three-phase pole voltage input of the active rectifier.

Abstract: Light load efficiency of a power factor correction circuit is improved by adaptive on-time control and providing for selection between a continuous conduction mode and a discontinuous conduction mode wherein the discontinuous conduction mode increases time between switching pulses controlling connection of a cyclically varying voltage to a filter/inductor that delivers a desired DC voltage and thus can greatly reduce the switching frequency at light loads where switching frequency related losses dominate efficiency. The mode for controlling switching is preferably selected for each switching pulse within a half cycle of the cyclically varying input voltage. A multi-phase embodiment allows cancellation of EMI noise at harmonics of the switching frequency and adaptive change of phase angle allows for cancellation of dominant higher order harmonics as switching frequency is reduced.

Abstract: Technique for controlling a circuit that converts an AC input voltage into a DC output voltage using transistors arranged in first and second transistor pairs. Each transistor of the first pair is controlled in accordance with polarity of the AC input voltage. Each transistor of the second pair is controlled based on a difference between the AC input voltage and the DC output voltage.

Abstract: Provided is a power conversion device capable of detecting a short circuit failure and protecting from the same securely. The power conversion device includes: a three-phase bridge type power conversion circuit including a semiconductor switch including a first main terminal, a second main terminal, and a control terminal; a control circuit for controlling an operation of the semiconductor switch; and a voltage detection circuit for monitoring a voltage between DC terminals of the power conversion circuit, in which the control circuit has a protection function of turning off the semiconductor switch if the voltage between the DC terminals of the power conversion circuit, which is detected by the voltage detection circuit, is lower than a predetermined value for a predetermined period of time or longer.

Abstract: Disclosed is a PFC (power factor correction) device for shaping an input current of a power converter. The device includes means for receiving a rectified input voltage derived from an AC input voltage; load determining means for determining a load value L which represents the power drawn by a load supplied by the power converter; current shaping means for shaping the input current of the power converter to follow a reference waveform; and control means for controlling the current shaping means to operate over a conduction interval ? during each positive and negative half cycle of the AC input voltage. The duration of the conduction interval is controlled in accordance with the load value L. The current shaping means may shape the input current to follow the reference waveform which crosses zero at phase angles which substantially correspond to the start and end of the conduction interval.

Abstract: A power converter includes an input stage connected to receive a three phase AC input voltage and to provide multiple DC voltage levels. The power converter also includes an output stage of a plurality of interleaved LLC converters having series-connected inputs coupled to the multiple DC voltage levels and parallel-connected outputs to provide a DC output voltage. Additionally, the power converter includes a balancing circuit interconnected to the input and output stages to provide substantially balanced output currents from the plurality of interleaved LLC converters for the DC output voltage. Methods of manufacturing and operating a power converter are also provided.

Abstract: A controller including a switch, a first module, a second module, and a control module. The switch receives current from an inductor and bypasses a portion of the current from being received by a load. The switch is cycled between a first state and a second state at a frequency. The first module, for a first cycle of the switch, determines a first amount of time the switch is in the first state. The second module, based on the first amount of time, determines a second amount of time for a level of the current to decrease to a predetermined level. The second amount of time begins during the first cycle and when the switch transitions from the first state to the second state. The control module, based on the second amount of time and prior to the current decreasing to the predetermined level, changes the frequency of the switch.

Abstract: A power supply apparatus mainly includes a secondary side controller, a digital isolator, a plurality of isolation sensing units, and a driving unit. The secondary side controller is configured to isolatedly measure voltages and currents, and is configured to isolatedly control the driving unit. The power supply apparatus includes a controller only, i.e. the secondary side controller 114. Therefore, the power consumption is lower, and the cost is lower. Only one controller is required to update software. There is no communication delay problem between two controllers.

Abstract: A light emitting element drive device includes an electric conduction switch that is provided along a power input line, a voltage detection unit that detects a power source voltage containing a noise component when the electric power is supplied to the power input line, a conversion processing unit that converts the detected power source voltage containing the noise component to a digital value, a data generation unit that generates data of a predetermined number of bits, and a control unit that turns on the electric conduction switch. The control unit determines a delay time based on the predetermined number of bits. The delay time corresponds to a time between supplying the electric power to the power input line and turning on the electric conduction switch. The control unit turns on the electric conduction switch after the delay time passes. Thus, an excessive rush current is prevented.

Abstract: Generally, this disclosure provides circuits and methods to reduce and regulate DC link voltage in a power supply through the use of a DC breaker circuit. The breaker circuit may include a breaker switch configured to couple an input stage circuit of a power supply to an output stage circuit of the power supply and to provide a regulated DC link voltage to the output stage circuit, the level of the DC link voltage based on switching states of the breaker switch. The breaker circuit may further include a control circuit configured to generate a gate control signal to control the switching states of the breaker switch, the gate control signal based on a comparison of the DC link voltage to a high voltage threshold and a low voltage threshold, such that the magnitude of the DC link voltage is regulated to a set point and a peak-to-peak ripple.

Abstract: In one embodiment, a synchronous rectifier controller is configured to initiate forming an off-time interval for a first period of time responsively to the controller forming a disable state of a switching signal wherein the control circuit maintains the switching signal in the disable state for at least the off-time interval. The controller is also configured to restart forming the off-time interval responsively to a voltage of a synchronous rectifier becoming a first value prior to expiration of the first period of time.

Abstract: The configurations of a bridgeless PFC circuit system and a controlling method thereof are provided. The proposed system includes a bridgeless PFC circuit including a first bridge arm having a first and a second terminals and a first middle point, a second bridge arm having a first and a second terminals and a second middle point, and a bidirectional switch coupled between the first middle point and the second middle point, and an inductor coupled between the first middle point and an AC power source coupled to the second middle point, and a current sensing circuit including a first current transformer sensing a first current flowing through the bidirectional switch, which having a primary side winding coupled to the bidirectional switch and a first and a second secondary side windings, and a switching device coupled to the two secondary side windings.

Abstract: According to one embodiment, a power conversion apparatus includes a first LC circuit, a first switch, a second switch, a smoothing capacitor, a second LC circuit and a controller. The first switch is connected to the AC power supply through the first LC circuit. The second switch is connected in series to the first switch. The smoothing capacitor is connected in parallel to a series circuit of the first switch and the second switch. The second LC circuit is connected between a connection point between the first switch and the second switch and a load. The controller outputs a first pulse signal to the first switch when a voltage polarity of the AC power supply is positive, and outputs a second pulse signal to the second switch when the voltage polarity is negative.

Abstract: There is provided a switching mode power supply having primary and secondary induction coils inductively coupled to each other and converting a voltage applied to the primary induction coil to supply the converted voltage to the secondary induction coil, the switching mode power supply including a power switching unit switching the voltage applied to the primary induction coil, a load information obtaining unit obtaining load information relating to a load connected to the secondary induction coil, a bias current controlling unit controlling a switching driving current based on the load information; and a driving unit driving the power switching unit based on the load information and the switching driving current.

Abstract: Electronic devices require correct power in order to operate correctly. Receiving an incorrect power signal could potentially result in immediate and/or long term harm to the electronic device and/or catastrophic conditions. Certain devices, such as programmable logic controller (“PLC”) modules, may provide variable power to electronic devices, such as field devices comprising sensors and/or actuators. The present inventors have recognized that deciphering between AC and DC input signals before coupling electronic devices to such power sources may advantageously avoid harmful and/or catastrophic conditions. Aspects of the present invention provide an electronic circuit for deciphering between an AC and a DC input signal. Systems and methods are also described.

Abstract: A power converter (such as a battery charger) includes a cable configured to deliver a source voltage and current to a load, where the cable is anticipated to drop some voltage as the load current increases. The power converter also includes a regulator having a feedback-adjusting transistor configured to gradually compensate for the dropped cable voltage as the load current increases. The transistor has a gate capacitance and a resistance forming an integrator configured to filter a volt-second product of an output waveshape of the converter to derive an average voltage correlated to the load current as the load current increases. The regulator is configured to increase a gate voltage of the transistor through a threshold region of the transistor and gradually turn the transistor on. The transistor is configured to apply an adjusting resistance coupled to a feedback sensing node of the regulator to increase the source voltage to compensate for the cable voltage drop and improve the load voltage regulation.

Abstract: There are provided a power factor correction apparatus and a power supply apparatus, the power supply apparatus including a power supply unit switching input power to supply preset driving power to a load, and a control unit providing a switching control signal having a preset number of pulses for a predetermined time to the power supply unit to control power switching of the power supply unit, and when a voltage level of the driving power is equal to or higher than that of at least one intermediate voltage set between a preset normal operating voltage and a preset abnormal operating voltage, skipping a portion of the number of pulses of the switching control signal for the predetermined time.

Abstract: A three-phase boost-buck PFC converter including three independent single-phase boost-buck PFC circuits respectively is provided, which are capable of performing PFC on each phase of the three-phase power. The single-phase boost-buck PFC circuit is composed of two single-phase boost-buck converters independently working in a positive and a negative half cycle of an input voltage, and the two single-phase boost-buck converters are connected in parallel at an input side, and are connected in series at an output side, and each of the single-phase boost-buck converters is composed of a front-end boost circuit and a back-end buck circuit connected in cascade. Compared to the existing technique, regardless of a boost mode or a buck mode, the conduction loss is effectively reduced, and the whole system efficiency is effectively improved.

Abstract: Disclosed herein are a blanking control circuit for controlling a synchronous rectifier and a method of controlling the synchronous rectifier by using the blanking control circuit. The blanking control circuit for controlling a synchronous rectifier includes: a power generating unit that receives power from the outside to generate a reference voltage and a bias current that are used in an integrated circuit (IC); a driving unit that receives the reference voltage and the bias current generated by using the power generating unit to generate a voltage for driving a switch of the synchronous rectifier; and a load sensing unit that determines a state of a load by sensing an output voltage of the synchronous rectifier driven by the driving unit, and generates a corresponding signal if the state of the load is in a low load state so as to turn off the switch of the synchronous rectifier.

Abstract: In one embodiment, an apparatus for performing power factor correction is provided. A power factor corrector includes an input configured to sense a current from an input circuit. A reference generator generates a current limit based on an input voltage. The current limit reference is dynamically changed based on the input voltage. A control signal generator controls the current in the input circuit based on a comparison of the current and the generated current limit.

Abstract: In one embodiment, an AC-DC power converter can include: (i) a rectifier bridge and filter to convert an external AC voltage to a DC input voltage; (ii) a first energy storage element to store energy from the DC input voltage via a first current through a first conductive path when in a first operation mode; (iii) a second energy storage element configured to store energy from a second DC voltage via a second current through a second conductive path when in the first operation mode; (iv) a transistor configured to share the first and second conductive paths; (v) the first energy storage element releasing energy to a third energy storage element and a load through a third conductive path when in a second operation mode; and (vi) the second energy storage element releasing energy to the load through a fourth conductive path during the second operation mode.

Abstract: A power supply device controls drive of a synchronous rectification switch unit by converting a voltage into a current, and comparing a voltage obtained by current-to-voltage conversion with a predetermined value.

Abstract: A switching power supply device includes: a fundamental wave component extraction circuit for extracting a fundamental wave component of a voltage induced across a first winding; an oscillator for generating a clock signal having an oscillation frequency that changes according to a change in the fundamental wave component; and a control circuit for (i) generating a control signal for controlling a switching element to be in an ON state or OFF state, the switching signal having a duty that changes according to a change in the oscillation frequency of the clock signal or a change in a voltage of a smoothing capacitor and (ii) supplying the control signal to a gate of the switching element.

Abstract: Embodiments of the subject invention relate to a method and apparatus for providing a low-power AC/DC converter designed to operate with very low input voltage amplitudes. Specific embodiments can operate with input voltages less than or equal to 1 V, less than or equal to 200 mV, and as low as 20 mV, respectively. Embodiments of the subject low-power AC/DC converter can be utilized in magnetic induction energy harvester systems. With reference to a specific embodiment, a maximum efficiency of 92% was achieved for a 1 V input, and efficiencies exceeding 70% were achieved for a 200 mV input. A specific embodiment functioned properly when connected to a magnetic energy harvester device operating below 200 mV input.

Abstract: Circuits and methods for generating a reference voltage for a power converter control are disclosed herein. The power converter control providing a signal on an output for aligning the voltage and current on a power line so that they are in phase. An embodiment of a circuit includes a voltage detector that detects the voltage on the power line. A signal generator generates a wave that is in phase with voltage on the power line, the wave being generated independent of the voltage on the power line. The output of the signal generator is the reference voltage.

Abstract: A power supply controller includes a switching signal generator, a zero crossing detection (ZCD) circuit, first and second logic gates, and an interval generator. The switching signal generator generates a switching signal and the ZCD circuit generates a ZCD signal that pulses each zero-crossing of an ac input voltage. The first logic gate generates a first output when the ZCD signal pulses while the output of the power supply is below a threshold reference. The second logic gate generates a second output when the ZCD signal pulses while the output of the power supply is above the threshold reference. The interval generator is enabled in response to the first output and disabled in response to the second output. The interval generator allows the switching signal to pass through the interval generator to the switch when enabled and does not allow the switching signal to pass when disabled.

Abstract: The present invention relates to a master-slave interleaved BCM PFC controller for controlling a PFC circuit with master and slave channels. In one embodiment, the PFC controller can include: a master channel controller that generates a master channel control signal and an inverted master channel control signal; a first phase shifter that provides a first phase shift for the master channel control signal, and generates a delayed opening signal therefrom; a second phase shifter that provides a second phase shift for the inverted master channel control signal, and generates a delayed shutdown signal therefrom; a slave channel controller that receives the delayed opening signal, the delayed shutdown signal, and a slave channel inductor current zero-crossing signal, and generates a slave channel control signal therefrom.

Abstract: In a controller for a power converter, a control terminal can provide a control signal to control a power converter. A cycle of the control signal includes a first time interval and a second time interval. The control circuitry can increase a primary current flowing through a primary winding of transformer circuitry and a secondary current flowing through a secondary winding of the transformer circuitry in the first time interval, and can terminate the increasing of the primary current in the second time interval. The control circuitry can also control the first time interval to be inversely proportional to an input voltage provided to the primary winding.

Abstract: A power factor control circuit has a power factor controller that determines if the power factor control circuit is operated at a continuous current mode (CCM) or a discrete current mode (DCM), and outputs PWM signals corresponding to the present current mode. A duty cycle of the PWM signals is equal to a sum of a feed-forward control parameter and a current compensation parameter. The current compensation parameter contains a difference value between a reference current and an inductor current in the power factor control circuit. Accordingly, a switching power supply circuit can acquire the PWM signals corresponding to the present current mode to effectively resolve the issue of harmonic distortion.

Abstract: An image forming apparatus is disclosed that includes a power storage unit. The power storage unit includes a constant voltage generation part configured to generate a constant voltage from a commercial power supply, the constant voltage generation part being connected to an external apparatus operating by consuming power; a voltage increasing circuit configured to increase the constant voltage generated by the constant voltage generation part; a capacitor configured to store an electric charge supplied from the voltage increasing circuit; a circuit control part configured to control charging of the capacitor; and an output part configured to output power stored in the capacitor, the power having a voltage different from the constant voltage.

Abstract: The present invention relates to reference voltage regulating methods and circuits for a constant current driver. In one embodiment, a method can include: setting a reference voltage circuit matching with a current output channel of a constant current source; setting a first resistor of the reference voltage circuit to follow an ideal equivalent resistor of the current output channel, and maintaining a proportion of the first resistor and the ideal equivalent resistor to be no less than a predetermined value M; setting a first current of the reference voltage circuit to follow an ideal output current of the current output channel, and maintaining a proportion of the first current and the ideal output current to be no less than 1/M; and setting a product of the first current and the first resistor to be a reference voltage of the reference voltage circuit.

Abstract: The disclosed embodiments provide an AC/DC power converter that converts an AC input voltage into a DC output voltage. This AC/DC power converter includes an input rectifier stage which rectifies an AC input voltage into a first rectified voltage of a first constant polarity and a first amplitude. The AC/DC power converter also includes a switching resonant stage which is directly coupled to the output of the input rectifier stage. This switching resonant stage converts the rectified voltage into a second rectified voltage of a second constant polarity and a second amplitude. The AC/DC power converter additionally includes an output rectifier stage coupled to the output of the switching resonant stage, wherein the output rectifier stage rectifies the second rectified voltage into a DC voltage output.

Abstract: A full-bridge power converter is provided. A control unit 30 generates control signals for individual switching elements for controlling ON/OFF operation of switching elements 11˜14, alternately turns the switching element 11 and switching element 12 ON/OFF, also alternately turns the switching element 13 and switching element 14 ON/OFF, outputs supply current from a full-bridge circuit 10 for supplying to a load 3, and, during a period when the supply current is not supplied, turns ON both the switching element 11 and switching element 13 to pass inertial current by discharging energy stored in inductors 16 and 17, and filter capacitors 19 and 20 absorb the charge of common-mode noise components appearing on an output line connecting the inductor 16 and an output capacitor 18 and on an output line connecting the inductor 17 and the output capacitor 18.

Abstract: An integrated circuit (IC) comprises a rectifier/regulator circuit coupled to receive an ac source voltage and output a regulated dc voltage. The rectifier/regulator circuit includes first and second switching elements that provide charging current when enabled. The first and second switching elements do not provide charging current when disabled. A sensor circuit is coupled to sense the regulated dc voltage and generate a feedback control signal coupled to the rectifier/regulator circuit that enables the first and second switching elements when the regulated do voltage is above a target voltage, and disables the first and second switching elements when the regulated do voltage is below the target voltage.

Abstract: A power conversion controller for controlling the operation of a switch in a power conversion circuit, wherein the power conversion controller is configured to operate the switch according to: a variable frequency mode of operation for switching frequencies greater than a minimum threshold value; and a fixed frequency mode of operation at a switching frequency equal to the minimum threshold value.

Abstract: Circuits and methods relating to the provision of a reactive current to ensure zero voltage switching in a boost power factor correction converter. A simple passive circuit using a series connected inductor and capacitor are coupled between two phases of an interleaved boost PFC converter. The passive circuit takes advantage of the 180° phase-shift between the two phases to provide reactive current for zero voltage switching. A control system for adjusting and controlling the reactive current to ensure ZVS for different loads and line voltages is also provided.

Abstract: Systems and methods for increasing power measurement accuracy for power factor correction (PFC) are disclosed. An exemplary method may include providing a PFC circuit for a power supply, the PFC circuit having a bulk capacitor connected to a rectified AC line. The method may also include measuring output load. The method may also include enabling AC wave skipping if the measured output load drops below a threshold value.

Abstract: In a steady state operation mode, a charging circuit of a non-isolated AC-to-DC converter decouples an output voltage VO node from a VR node when the rectifier output signal VR on the VR node is greater than a first predetermined voltage VP and, 2) supplies a charging current from the VR node and onto the VO node when VR is less than VP provided that an output voltage VO on the VO node is less than a second predetermined voltage VO(MAX) and provided that VR is greater than VO. In an initial power up operation mode, the maximum limit value of the charging current is smaller than it is during steady state operation. Due to the reduced charging currents employed during initial power up operation, less noise is injected back to the AC source and EMI filters are not required between the rectifier of the converter and the AC source.

Abstract: A power factor correction device comprises a power stage circuit converting input alternating current voltage into input current according to a pulse width modulation signal and outputs the input current to a load generating output voltage on the load, and sampling the input current outputting a correcting current; a current compensating circuit receiving and comparing the correcting current with a reference current signal generating a compensating current signal; a voltage compensating circuit receiving and comparing the output voltage with a reference voltage generating a compensating voltage signal; a multiplication amplifier receiving the compensating current signal and the compensating voltage signal generating an updated reference current signal by multiplying the compensating current signal with the compensating voltage signal; and a pulse width modulation converter receiving the compensating current signal and the compensating voltage signal generating the pulse width modulation signal to synchronize

Abstract: Bridgeless boost PFC circuits and systems providing an improved method of current sensing using two current sensing resistors is envisaged. Analog switches are provided to select one of the two current sensing resistors based on the polarity of the AC line. An amplifier is provided to eliminate use of resistors with large values, thus resulting in lower power loss and efficient systems.

Abstract: A power conversion circuit includes a voltage boost circuit configured to generate an output voltage in response to an input voltage, a boost controller configured to control operation of the voltage boost circuit, and a bias voltage generation circuit configured to generate a bias voltage. The bias generation circuit is configured to regulate a level of the bias voltage in response to a level of the input voltage.

Abstract: In one embodiment, an AC/DC power converter can include: a rectifier bridge and a filter capacitor for converting an external AC voltage to a half-sinusoid DC input voltage; a first storage component, where during each switching cycle in a first operation mode, a first path receives the half-sinusoid DC input voltage to store energy in the first storage component, and a first current through the first storage component increases; a second storage component, where a second path receives a second DC voltage to store energy in the second storage component, and a second current through the second storage component increases; and a third storage component, where in a second operation mode, the first current decreases to release energy from the first to the third storage component, where the second DC voltage includes a voltage across the third storage component through a third path.