Abstract: A voltage converter that receives at input a primary DC voltage that is variable over a wide voltage range and that supplies at output a regulated first secondary DC voltage and an unregulated second secondary DC voltage, including a buck converter with inductors coupled to two outputs, it also includes a boost converter arranged upstream of the buck converter and able to boost the primary voltage when activated, and a charge pump module arranged between the second secondary voltage and the first secondary voltage and able to balance the charges when activated, the boost converter and the charge pump module being activated simultaneously.

Abstract: A switched-capacitor power stage includes a first sub-power stage. The first sub-power stage includes a first inductor, a first high switch, a first low switch, and a first set of switched-capacitor networks. The first inductor is coupled to an input terminal. The first high switch is coupled between the first inductor and an output terminal. The first low switch is coupled between the first inductor and a first transition node. The first set of switched-capacitor networks is coupled between the first transition node and the output terminal.

Abstract: A multi-phase PFC (power factor correction) system, controller for the multi-phase PFC system and method of controlling the multi-phase PFC system are described. The controller includes a digital circuitry configured to calculate a delay value based on a positive current slope and a negative current slope for a first phase of the plurality of phases which is enabled for all load current conditions. In response to an increase in an average current reference, the digital circuitry is configured to enable a second phase of the plurality of phases such that a current output by the second phase is out of phase with a current output by the first phase by an amount corresponding to the delay value as referenced to a beginning of a boost charging portion of a switching cycle for the first phase.

Abstract: The invention disclose a power supply circuit. The power supply circuit includes one or a plurality of first-stage voltage conversion circuits and one or a plurality of second-stage voltage conversion circuits; an input end of the first-stage voltage conversion circuit is coupled to a power supply; the first-stage voltage conversion circuit is configured to convert a first voltage received at the input end into a second voltage, where the second voltage is less than the first voltage; an input end of the second-stage voltage conversion circuit is coupled to an output end of the first-stage voltage conversion circuit; the second-stage voltage conversion circuit is configured to convert the second voltage into a third voltage, and supply the third voltage to a load.

Abstract: Provided is a voltage generation circuit for improving the characteristics of a high-side switching element by applying an appropriate control power supply voltage to the high-side drive circuit. The voltage generation circuit includes a bootstrap circuit and a step-down circuit. The bootstrap circuit includes a diode and a current limiting resistor. The step-down circuit is connected to a high potential side of the high-side switching element and an input side of the bootstrap circuit. The step-down circuit outputs a compensated power supply voltage generated by stepping down a power supply voltage applied to the high potential side of the high-side switching element to the bootstrap circuit. The step-down circuit generates the compensated power supply voltage obtained by adding a compensation voltage corresponding to a voltage drop due to the diode and the current limiting resistor to a control power supply voltage for a low-side drive circuit.

Abstract: The invention disclose a power supply circuit. The power supply circuit includes one or a plurality of first-stage voltage conversion circuits and one or a plurality of second-stage voltage conversion circuits; an input end of the first-stage voltage conversion circuit is coupled to a power supply; the first-stage voltage conversion circuit is configured to convert a first voltage received at the input end into a second voltage, where the second voltage is less than the first voltage; an input end of the second-stage voltage conversion circuit is coupled to an output end of the first-stage voltage conversion circuit; the second-stage voltage conversion circuit is configured to convert the second voltage into a third voltage, and supply the third voltage to a load.

Abstract: A low-dropout regulator architecture with undershoot mitigation. In one embodiment, a system including a low-dropout regulator and a digital-to-analog converter (DAC). The low-dropout regulator is configured to generate a load current and output a voltage at an output node. The digital-to-analog converter (DAC) is configured to receive a control input, and output a DAC current to the low-dropout regulator based on the control input. The DAC current is configured to modify the load current and mitigate an undershoot of the voltage that is output at the output node while the voltage transitions from a high voltage level to a low voltage level.

Abstract: Various implementations described herein are directed to systems, apparatuses and methods for operating stand-alone power systems. The systems may include power generators (e.g., photovoltaic generators and/or wind turbines), storage devices (e.g., batteries and/or flywheels), power modules (e.g., power converters) and loads. The methods may include various methods for monitoring, determining, controlling and/or predicting system power generation, system power storage and system power consumption.

Abstract: Detection circuitry for an integrated circuit (IC) includes voltage divider circuitry, comparison circuitry, and calibration circuitry. The voltage divider circuitry receives a power supply signal and output a first reference voltage signal and a supply voltage signal based on the power supply signal. The comparison circuitry compares the first reference voltage signal and the supply voltage signal to generate an output signal. The calibration circuitry alters one or more parameters of the voltage divider circuitry to increase a voltage value of the supply voltage signal based on the comparison of the first reference voltage signal with the supply voltage signal.

Abstract: A power system includes a power conversion stage that receives power from an input source and delivers power to a load via a power distribution bus. The power distribution bus may include a DC transformer such as a fixed ratio bus converter or VTM having an equivalent series resistance. A control system samples the voltage delivered by the power conversion stage at a location close to the output of the power conversion stage, and the load voltage at a location close to the load. The samples may be synchronized by means of a data bus that provides communication between a control device and an output monitor. Synchronization may be accomplished within a sampling period that is short relative to changes in the voltages and currents. Each set of samples may be used to determine a value of the bus resistance. Multiple samples may be averaged to improve accuracy in the determination.

Abstract: A current sensing technique for coupled inductors in switching regulator circuits, where the current sensing technique can provide the current information needed for a power converter design and can be implemented as a real-world solution. The current sensing techniques can provide complete information of the coupled inductor current, such as peak current, valley current, and intermediate ripples. The current sensing techniques can use a simple RC network, such as two resistors and two capacitors for 2-phase operation. The techniques, however, are not limited to two-phase operation. The current sensing techniques of this disclosure can be extended to power stage assembly implementations, e.g., DrMOS modules, with current output in order to increase signal-to-noise ratio, which is significant for reliable control. In addition, the current sensing techniques of this disclosure can be extended to multi-phase operation, such as three or more phases.

Abstract: A Hybrid DC-DC switching converter architecture is described. The Hybrid architecture includes a capacitive converter cascaded by an inductive converter for a boost switching converter, and an inductive converter cascaded by a capacitive converter for a buck switching converter. A capacitor at an intermediate node and a switch in the capacitive converter are removed. Reducing the switching converter by one switch and one capacitor results in a smaller implementation area. A single regulation circuit and an inductor with a smaller saturation current (Isat) are used.

Abstract: Certain aspects of the present disclosure generally relate to a connection terminal pattern and layout for a three-level buck regulator. One example electronic module generally includes a substrate, an integrated circuit (IC) package disposed on the substrate and comprising transistors of a three-level buck regulator, a capacitive element of the three-level buck regulator disposed on the substrate, and an inductive element of the three-level buck regulator disposed on the substrate. In certain aspects, the capacitive element and the inductive element may be disposed adjacent to different sides of the IC package.

Abstract: A dual-stage boost converter is disclosed. The boost converter includes a charge pump and a boost stage. The charge pump is coupled between an input voltage source and the boost stage. The charge pump is coupled to receive the input voltage and configured to generate an intermediate voltage that is greater than the input voltage received from the input voltage source. The boost stage includes an inductor coupled to receive the intermediate voltage and is configured to generate an output voltage that is greater than or equal to the intermediate voltage.

Abstract: The present document relates to a power converter configured to generate an output voltage at an output of the power converter. The power converter may comprise a power stage, a modulator circuit, ramp generator circuit, a first feedback circuit, and a second feedback circuit. The power stage may be coupled to the output of the power converter. The modulator circuit may comprise a first input and a second input, and an output of the modulator circuit may be coupled to the power stage. The ramp generator circuit may be configured to generate a ramp signal, and an output of the ramp generator circuit may be coupled to the first input of the modulator circuit. The first feedback loop may be coupled between the output of the power converter and the second input of the modulator circuit.

Abstract: A power supply is configured to perform an at least partial compensation of a voltage variation caused by a load change using a voltage variation compensation mechanism which is triggered in response to an expected load change. An Automated test equipment for testing a device under test comprises a power supply, which is configured to supply the device under test. The automated test equipment comprises a pattern generator configured to provide one or more stimulus signals for the device under test. The power supply is configured to perform an at least partial compensation of a voltage variation caused by a load change using a voltage variation compensation mechanism which is activated in synchronism with one or more of the stimulus signals and/or in response to one or more response data signals from the device under test. Corresponding methods and a computer program are also described.

Abstract: A power conversion apparatus with dual-mode control includes a bridge arm assembly, a capacitor assembly, and control unit. The bridge arm assembly includes a first bridge arm and a second bridge arm. The control unit selectively controls the first bridge arm to be operated in a voltage source switching mode or a current source switching mode according to the load type of a first load, and controls the second bridge arm to be operated in the voltage source switching mode or the current source switching mode according to the load type of a second load.

Abstract: A power delivery system may include a first voltage regulator configured to output an upper intermediate voltage about an expected discharge voltage plateau of a battery for use by the power delivery system, a switched capacitive charge pump configured to down convert the upper intermediate voltage of the first voltage regulator to a lower intermediate voltage, and a second voltage regulator configured to use the lower intermediate voltage to provide power to a load.

Abstract: A switching power regulator and method for recovering the regulator from an unregulated state while preventing overshoot of an output voltage is provided. The regulator includes a dropout detector, a sample-and-hold circuit, a voltage offset circuit and a soft start circuit. When the regulator enters an unregulated state, the dropout detector detects when a pulse width modulation (PWM) signal stops toggling. The sample-and-hold circuit and soft start circuit are used to effectively clamp the voltage at the output of an error amplifier. This causes the output of the error amplifier to regulate around a desired voltage so that the regulator recovers from the unregulated state with little or no overshoot of the output voltage. In another embodiment, a method for recovering from the unregulated state is provided.

Abstract: A power conversion device includes a plurality of conversion units electrically connected in parallel to each other and configured to perform voltage conversion of electric power supplied from a power supply and a control device configured to set a conversion unit that will operate within the plurality of conversion units, wherein, after the number of conversion units that are operating within the plurality of conversion units is increased, the control device makes an electric current flowing through an operation start conversion unit which is a conversion unit that has started to operate from a non-operating state larger than an electric current flowing through an operation maintenance conversion unit which is a conversion unit that continues to operate before and after the number of operating conversion units is increased.

Abstract: A control method is provided for controlling an electronic device having a main body. The control method may include: in response to the electronic device being activated and a primary battery being functionally connected to the main body of the electronic device, controlling the primary battery to power the electronic device; and in response to the electronic device being activated and the primary battery being functionally disconnected from the main body of the electronic device, controlling a backup battery to power the electronic device.

Abstract: A Method and apparatus for control of switch mode power supplies utilizing magnetic and capacitive conversion means are disclosed. The switch mode power supply is efficient and generates very small inductor current ripple and output voltage ripple. The switch mode power supply has a wider bandwidth and the filter components including magnetic storage element and the output capacitor can be made much smaller. The capacitor voltages in the switched capacitor array are regulated by changing the amount of time the inductor current passes through them.

Abstract: Methods and apparatus are disclosed relating to the stimulating of tissue including nerve tissue based on combinations of capacitors and resistors. Application and removal of voltage to an electrical circuit is taught as part of a method of creating voltage waveforms for nerve and other tissue with such waveforms creating neural signals. The electrical apparatus taught may, include a first electrical node grounded through a first resistor; a second electrical node grounded through a second resistor; a first capacitor connected to both the first electrical node and the second electrical node; a second capacitor separating the second electrical node from a biological grounding point and direct current sources connected to the two nodes.

Abstract: A power supply continuity system that maintains power continuity of a system, for example, a power tool. A reserve power supply, such as a capacitor, is operably coupled to a primary power supply in a parallel configuration to provide power to the system when the primary power supply is inoperable or disconnected. The reserve power supply can also be implemented in power regulation circuitry, for example, circuitry that controls the power output of the primary power supply, so that the reserve power supply can be included on a printed circuit board (PCB) and decrease costs of manufacturing.

Abstract: A circuit includes a voltage detection path having a first transistor and a second transistor coupled to the first voltage detection path by a first terminal of the second transistor. The first voltage detection path includes: a first current source and a first voltage divider unit coupled to the first current source. The first transistor is coupled to the first voltage divider unit by a first terminal of the first transistor. A first voltage value at a second terminal of the first transistor is configured to switch between a first high voltage value and a first low voltage value at least partially based on a first detection voltage value provided at the first terminal of the first transistor by the first voltage divider unit. A second voltage at a second terminal of the second transistor is configured to switch between a second high voltage value and a second low voltage value at least partially based on the first voltage value at the second terminal of the first transistor.

Abstract: A power system includes a power conversion stage that receives power from an input source and delivers power to a load via a power distribution bus. The power distribution bus may include a DC transformer such as a fixed ratio bus converter or VTM having an equivalent series resistance. A control system samples the voltage delivered by the power conversion stage at a location close to the output of the power conversion stage, and the load voltage at a location close to the load. The samples may be synchronized by means of a data bus that provides communication between a control device and an output monitor. Synchronization may be accomplished within a sampling period that is short relative to changes in the voltages and currents. Each set of samples may be used to determine a value of the bus resistance. Multiple samples may be averaged to improve accuracy in the determination.

Abstract: A power management device is disclosed, including a first DC-DC converter coupled to a first output voltage line, a second DC-DC converter coupled to a second output voltage line, a first set of switches associated with the first DC-DC converter, and a second set of switches associated with the second DC-DC converter. The power management device may further include a controller configured to toggle one or more switches of the first set of switches and one or more switches of the second set of switches, and a multi-mode radio-frequency front-end block communicatively coupled to the controller.

Abstract: In one embodiment, a semiconductor device includes a reference voltage supply circuit configured to supply a first reference voltage and a second reference voltage. The device further includes a power source voltage supply circuit including a first power source voltage generator supplied with the first reference voltage and configured to generate a first power source voltage, and a second power source voltage generator supplied with the second reference voltage and configured to generate a second power source voltage, the power source voltage supply circuit being configured to supply the first power source voltage and the second power source voltage to a power source voltage line. The device further includes a voltage control circuit connected to the power source voltage line, and configured to control a value of the first reference voltage and a value the second reference voltage.

Abstract: A wireless-power-transmission-system includes a bridge with a tank-capacitor coupled thereto, a sense-resistor coupled between the bridge and an input of a regulator, a switching-circuit having first and second inputs coupled across the sense-resistor, and a gain-stage having first and second inputs capacitively coupled to first and second outputs of the switching-circuit. An ADC digitizes output of the gain-stage by comparing the output to a reference voltage, and a temperature-independent current source is coupled to a reference-resistor to generate the reference voltage. In a reset-phase, the switching-circuit shorts the inputs of the gain-stage to one another, and the gain-stage shorts its inputs to its output. The switching-circuit, in a first-chopping-phase, couples the sense-resistor between the first and second inputs of the gain-stage, and in a second-chopping-phase, couples the sense-resistor in reverse between the second and first inputs of the gain-stage.

Abstract: The present disclosure discloses a switching regulator circuit comprising: a series regulator having at least one regulating transistor with the connections collector, base and emitter; and a DC-DC converter, in particular a step-down converter, which is connected downstream of the series regulator, wherein the switching regulator circuit is designed such that the DC-DC converter is regulated to a constant collector-emitter voltage drop across the regulating transistor; in particular, the DC-DC converter is activated such that a constant collector-emitter voltage drop results. In addition, the present disclosure also discloses a corresponding method.

Abstract: Exemplary embodiments are related to a buck regulator. A buck regulator may include an inductor selectively coupled to an output and a power supply. The regulator may also include a controller configured to detect an over-current event if an amount of current flowing from the power supply to the inductor is equal to or greater than a current threshold and detect a low-voltage event if a voltage at the output is less than or equal to a reference voltage. Further, in response to the over-current event and the low-voltage event, the controller may be configured to prevent current from flowing from the power supply to the inductor until substantially all energy stored by the inductor has been dissipated.

Abstract: A power supply configured to supply a modulated voltage to a power amplifier is shown. The power supply has an alternating current (AC) component generator, a direct current (DC) component generator, and a transition accelerator. The AC component generator generates an AC component of the modulated voltage according to an envelope tracking signal. The DC component generator generates a DC component of the modulated voltage according to the operational voltage range of the power amplifier. The transition accelerator is coupled to an output terminal of the DC component generator to speed up the transition of the modulated voltage.

Abstract: A power converter is provided. The power converter includes a switched-capacitor conversion circuit and an inductor buck circuit. The switched-capacitor conversion circuit receives an input voltage and operates according to a first operation frequency to convert the input voltage to an intermediate voltage. The inductor buck circuit is coupled to the switched-capacitor conversion circuit in series. The inductor buck circuit receives the intermediate voltage and operates on a second operation frequency to generate an output voltage at a conversion output terminal according to the intermediate voltage. The first operation frequency is determined according to the second operation frequency.

Abstract: Circuits and methods to enable wireless power transmission and reception are presented. A two-stage power converter has a boost regulator to boost an input voltage to an intermediate voltage. Moreover, the two-stage power converter may also comprise a charge pump coupled to the boost regulator to generate an output voltage based on the intermediated voltage. More particularly, the charge pump may comprise a plurality of transistor devices and a flying capacitor and the charge pump may be bypassed during a bypass mode of operation. Finally, the two-stage power converter may have control circuitry coupled to the charge pump. In particular, the control circuitry may generate a control voltage of a first transistor device of the plurality of transistor devices in order to regulate a discharge rate of the flying capacitor, during a transition phase from the bypass mode of operation to a normal mode of operation.

Abstract: Various embodiments of a fault detector for a voltage converter are described. In one example embodiment, briefly, the fault detector is capable to detect one or more fault events during operation of a voltage converter. Likewise, the fault detector is capable to generate one or more fault signals with respect to the one or more to be detected fault events. The one or more fault signals, in the example embodiment, to signal a disconnect switch of the voltage converter to electrically disconnect or otherwise via a high impedance state to limit current flow through at least one switch of a set of switches of the voltage converter. In another example embodiment, the fault detector, responsive to the one or more fault signals, capable to generate a bus interrupt signal on a pin out, such as of an integrated circuit (IC) for use with the voltage converter, or capable to toggle a fault indicator pin out of the IC. Other additional embodiments are also described.

Abstract: The disclosure describes techniques for measuring the average output current of a power converter circuit by determining peaks valleys in the output current. A current monitoring circuit may include an averaging unit, which may sample the output current during a current peak as well as during a current valley. During a hold phase the averaging unit may output a signal proportional to the average output current based on the sampled peak current and sampled valley current. In some examples, the averaging unit may include three functional units. A first unit may be configured to determine the output current, a second block may be configured to hold the previously determined peak current and a third block may be configured to hold the previously determined valley current. In this manner the averaging unit may continuously output a signal proportional to the average output current of the power converter.

Abstract: In one or more embodiments, an efficient scheme is provided for sampling inductor currents in a digital multiphase PWM controller used for high-bandwidth voltage regulation. Some embodiments use the data from the PWM modulator along with weighted states based on the PWM waveform and past conversions in order to prioritize which current sense input should be sampled for each conversion. In these and other embodiments, a single ADC is used to sample inductor currents from two or more phases in a multiphase PWM controller, thereby providing power and area savings, for example.

Abstract: Provided are electrical circuits and methods for power factor correction. An example method includes receiving, by converter, an input voltage at a fundamental frequency and generating an output voltage; generating, based on the output voltage, a first measurement signal; subtracting a first reference signal from the first measurement signal to obtain a first error signal; generating an adaptive current sense signal, generating a reference voltage based on the input voltage, subtracting the reference voltage from the current sense signal thus generating a second measurement signal to control the current measurement; subtracting the second measurement signal from the input voltage to obtain a difference signal, wherein the difference signal is largely minimized by removing overtones of the fundamental frequency; generating, based on the difference signal, a second error signal; using a sum of the second error signal as a first order correction to the first error signal to regulate the converter.

Abstract: A circuit comprising a first processing element having a first output configured to couple to a voltage control circuit, a second output configured to couple to a gate terminal of a first transistor, and a third output configured to couple to a first node and a control circuit. The control circuit comprises a second processing element having multiple outputs, a second transistor having a gate terminal configured to couple to one of the outputs of the second processing element, a first terminal configured to couple to a second node and to a drain terminal of the first transistor, and a second terminal, and a third transistor having a gate terminal configured to couple to a second of the outputs of the second processing element, a first terminal configured to couple to a third node, and a second terminal.

Abstract: An improved AC direct to DC extraction conversion system is described. The AC direct to DC extraction conversion system consists of an efficient electronic switch employed to provide controlled pulsed power to a storage device. The AC to DC converter in one minimal version consists of a pair of N-MOSFET transistors, a voltage divider, a storage element and a pair of diodes. The design enables high efficiency with minimal components that may be fully integrated onto silicon.

Abstract: Provided is a power distribution system that includes a reconfigurable DC/DC power converter configured to be connected with an energy storage device at an input end for receiving an input voltage therefrom, and a power electronics building block having a primary bridge unit, a secondary bridge unit magnetically connected with the primary bridge unit, and an outer bridge unit at an output end and connected to an output of the secondary bridge unit, configured to output an output voltage.

Abstract: A method for providing an output power of a switched mode power converter comprises the steps of determining a block length and, if a set value of the output power is below a first power threshold, preventing a power flow through the converter in each period of the multiphase AC voltage for at least one blocking interval. Each blocking interval has a duration of one block length. The switched mode power converter has a multiphase AC side with a number N of conductors for receiving a multiphase AC voltage. The number N of conductors is at least three. Power flows into the switched mode power converter through a combination of current-carrying conductors. The block length is defined by a time span between two subsequent changes of the combination of the current-carrying conductors.

Abstract: A DC-to-DC converter includes at least one primary switch, a primary inductor, and a switch rectifier circuit or a switch flyback circuit. A switch driving circuit is structured to drive the at least one primary switch. A fault detection method includes directly or indirectly detecting a voltage waveform or a current waveform of at least one terminal of the primary inductor, and determining whether the at least one primary switch is in a diode rectifying state or in a diode flyback state based on the voltage waveform or the current waveform to detect whether there is a fault in the switch driving circuit.

Abstract: A method for current limiting an operational amplifier includes sensing a first current through a first branch of the operational amplifier. The first branch conducts the first current from a limited current supply connected to an operational amplifier output. The first current is compared to a reference current to generate a regulation signal. A variable current source is controlled with the regulation signal. An output current of a transconductance amplifier is limited with the variable current source to limit the first current in response thereto.

Abstract: Methods, systems, and apparatuses are disclosed for ultrasound imaging comprising Time Delay Spectrometry. A frequency swept signal can be transmitted through a medium, such as human tissue. The signal can be a low-voltage signal (e.g., 0 volts to 5 volts peak-to-peak) transmitted for long duration (e.g., 20 milliseconds) at various frequencies. As the signal propagates through the medium it can be reflected and delayed. A delay associated with the signal the can cause a change in the associated frequencies. The signal can be filtered to retain only frequencies in an audio frequency range. The signal can be beamformed and processed to produce an image.

Abstract: A power detect circuit is disclosed. A power detect circuit includes a voltage multiplier that receives an external supply voltage and generates a second supply voltage that is greater than the former. A voltage regulator is coupled to receive the second supply voltage and outputs a regulated supply voltage. A bandgap circuit is coupled to receive the second supply voltage when a first switch is closed, and the regulated supply voltage when a second switch is closed. The bandgap circuit generates a reference voltage for the voltage regulator, as well as one or more output voltages. A comparator circuit is coupled to receive the one or more output voltages from the bandgap circuit, and may compare these one or more output voltages to the regulated supply voltage.

Abstract: A power converter and a method for receiving an input voltage and providing an output voltage is presented. The power converter has a switching circuit to generate the output voltage. The switching circuit has a first switch, a switch control circuit arranged to selectively operate the first switch in a first state or a second state. There is a ripple reduction circuit to set a first state duration based on a property of a load current. The load current is a current that the power converter provides to a load that is coupled to the output voltage.

Abstract: A hybrid energy storage module (HESM) configured to be used on an aircraft to provide electrical energy may include a battery and an ultracapacitor each configured to receive the electrical energy, store the electrical energy, and discharge the electrical energy, a power bus in electronic communication with the battery and the ultracapacitor, and a controller coupled to the battery and the ultracapacitor and configured to control charging and discharging of the battery and of the ultracapacitor such that a measured voltage of the power bus is adjusted based upon at least one of a battery state of charge (SOC) or an ultracapacitor SOC.

Abstract: Disclosed is a system and method for large-current power supply and constant-current control. Large-current power supply includes: primary power supply, energy-feedback circuit and direct-current (DC) large-current generator; energy-feedback circuit includes freewheel diode and magnetic reset winding; and secondary coil of DC large-current generator is connected to load. Without output rectifier diode and filter capacitor at load end of large-current power supply provided herein, power consumption problem of output rectifier diode at large current is unnecessarily considered, and electrolytic capacitor is not needed for filtration; and therefore, service life of power supply is greatly prolonged, larger current is output by extending, and power supply has advantages of simple circuit, small size, easy control and high working reliability.

Abstract: An apparatus includes a first winding and a second winding on a core and having first taps coupled in common to a first node of an inverter circuit. The apparatus further includes a switching circuit configured to selectively couple a second tap of the first winding to a second node of the inverter circuit and to selectively couple a second tap of the second winding to a third node of the inverter circuit. The switching circuit may be configured to provide a desired balance of first and second voltages at respective ones of the second and third nodes with respect to the first node. Related methods are also described.