Abstract: A method includes making a determination at a user device to transition the user device to a standby mode. The method includes sending a message from the user device to a server of a service provider in response to the determination, where the service provider provides a service to the user device. The method includes receiving, in response to the message, a content stream at the user device. The method includes sending video content generated from the content stream to a display device while the user device is in the standby mode. The method also includes, in response to a time in the standby mode exceeding a threshold, transmitting a second message to the server from the user device. In response to the second message, receipt of the content stream ceases.

Abstract: A first partial power converter implementation receives and converts an input voltage into multiple auxiliary voltages including a first auxiliary voltage and a second auxiliary voltage. The first partial power converter produces a first output voltage as a first summation of the first auxiliary voltage and the input voltage; the first partial power converter produces a second output voltage as a second summation of the second auxiliary voltage and the input voltage. A second partial power converter implementation as discussed herein receives a first auxiliary input voltage referenced with respect to an output voltage of the power converter. The second partial power converter also receives a second auxiliary input voltage referenced with respect to the output voltage. The second partial power converter converts the first auxiliary input voltage and the second auxiliary input voltage into the output voltage to power a load.

Abstract: An inductor component is configured such that a lower surface of a first magnetic layer serves as a first terminal surface. A first inductor wire is disposed in the first magnetic layer. The first inductor wire is cylindrical and extends in an up-down direction. A boundary portion is connected to a first internal terminal of the first inductor wire. An upper surface of a second magnetic layer serves as a second terminal surface. A second inductor wire is disposed in the second magnetic layer. The second inductor wire is columnar and extends in the up-down direction. A second internal terminal of the second inductor wire is connected to the boundary portion. The boundary portion serves as a physical boundary between the first inductor wire and the second inductor wire.

Abstract: Related to is a bidirectional CLLC circuit with a coupled inductor, which is associated with a circuit topology and operation control of a bidirectional CLLC resonant converter. Provided is a structure of a bidirectional CLLC resonant circuit with a coupled inductor, including a primary side bridge, a secondary side bridge, a primary side resonant capacitor, a secondary side resonant capacitor, a coupled resonant inductor, and a transformer. Compared with a structure of a conventional bidirectional CLLC resonant circuit, two separate resonant inductors located at a primary side and a secondary side in an original resonant cavity are replaced with one coupled resonant inductor in the circuit; the coupled resonant inductor has opposite dotted terminals with the transformer, and a primary side and a secondary side of the coupled resonant inductor are respectively in serial connection with a primary side and a secondary side of the transformer.

Abstract: A vehicle inverter is arranged to transform direct current power from a power supply to alternating current power for an outlet. The inverter includes a transformer electrically connected between the power supply and outlet, a resistive element that can be selectively electrically connected in parallel with the transformer via a multiway switch to establish a direct electrical connection between the power supply and outlet, and a controller that selectively commands the multiway switch to close according to values indicative of resistance between the power supply and outlet before and after the multiway switch is closed.

Abstract: A method for wirelessly or conductively (non-wireless) providing AC or DC power in AC or DC load applications and bidirectional applications.

Abstract: A flying capacitor converter includes an inductor, a first switch and a second switch, a first diode and a second diode, a first capacitor and a second capacitor, a flying capacitor, a third diode and a third capacitor, a fourth diode, and a fifth diode. The inductor is coupled to a first node. The first switch and the second switch are commonly connected to a second node. The first diode and the second diode are commonly connected to a third node. The first capacitor and the second capacitor are commonly connected to a fourth node. The flying capacitor is coupled to the second node and the third node. The third diode and the third capacitor are commonly connected to a fifth node. The fifth diode is coupled to the third node and the fourth node.

Abstract: A method includes making a determination at a user device to transition the user device to a standby mode. The method includes sending a message from the user device to a server of a service provider in response to the determination, where the service provider provides a service to the user device. The method includes receiving, in response to the message, a content stream at the user device. The method includes sending video content generated from the content stream to a display device while the user device is in the standby mode. The method also includes, in response to a time in the standby mode exceeding a threshold, transmitting a second message to the server from the user device. In response to the second message, receipt of the content stream ceases.

Abstract: A charging apparatus may include a power factor correction converter including a switching element, to correct a power factor of AC power provided by external charging equipment through ON/OFF control of the switching element, to convert the corrected power factor into DC power, and to output the DC power; a DC link capacitor connected to both ends of the PFC converter to form a DC voltage; a DC-DC converter converting a magnitude of the DC voltage formed by the DC link capacitor into a magnitude of a voltage required by an energy storage device to be charged; and a duty controller configured to determine a duty of the switching element in the PFC converter based on a magnitude of a common-mode component of an AC voltage of the AC power provided by the external charging equipment and the magnitude of the DC voltage formed by the DC link capacitor.

Abstract: A current regulator for a pulsed load is provided herein. The current regulator may include: an input power source; a current sense circuit; a capacitive energy storage device; a current sink driver; a current source charger which receives input current from the input power source via the current sense circuit and provides a charge for the capacitive energy storage device coupled between the current source charger and the current sink driver which drives the pulsed load; a power monitor circuitry which generates a feedback signal, based on a function of the input power and a function of at least one of: voltage across the capacitive energy storage, or voltage across the current sink driver; and a pulse width modulation (PWM) or pulse frequency modulation (PFM) circuitry which controls the current source charger based on the feedback signal.

Abstract: A resonant converter is disclosed, including: a primary side circuit including at least one set of primary side switches, where the primary side circuit is configured to receive an input voltage; a resonant network coupled to the primary side circuit; a transformer having a primary side winding and a secondary side winding, where the primary side winding is coupled to the resonant network; a secondary side circuit including at least one set of secondary side switches, where the secondary side circuit is coupled to the secondary side winding of the transformer; and a control block that controls the secondary side switches according to the input voltage, the output voltage and the current detection signal, so that the secondary side winding of the transformer is short-circuited during a preset time interval before operating state of the primary side switches changes.

Abstract: In some implementations, there is provided an apparatus comprising a resonant amplifier circuit including a first inductor having a first inductive input and a first inductive output; a second inductor having a second inductive input and a second inductive output; a first switch coupled to the first inductive output; and a second switch coupled to the second inductive output, wherein the first switch and the second switched are driven out of phase, wherein the first inductor is configured to be resonant with a first capacitance associated with the first switch, and wherein the second inductor is configured to be resonant with a second capacitance associated with the second switch. Related systems and articles of manufacture are also provided.

Abstract: A resonant DC-DC converter for generating high voltage MHz bi-polar DC pulses includes a left multi-level resonant rectifier bank [100] connected to a positive electrode [104] and coupled via capacitive isolation to a left RF amplifier terminal [128]; a right multi-level resonant rectifier bank [102] connected to a negative electrode [106] and coupled via capacitive isolation to a right RF amplifier terminal [130]. Each multi-level resonant rectifier bank comprises multiple resonant rectifier stages [112-122], where each stage comprises two capacitors for capacitively isolating the stage, an output capacitor, a MOSFET switch connected to an adjacent MOSFET switch of an adjacent stage, and a gating resonant circuit connected to the MOSFET switch, whereby MOSFET switches in the banks can be passively controlled by RF signals from a left RF amplifier and a right RF amplifier.

Abstract: The alternating-current power supply device 1 has: an alternating-current generation bridge 10 for obtaining an alternating-current output; PWM control bridges 20, 30, each including two switch components; and a coupling reactor 40 connected to the PWM control bridges 20, 30. The coupling reactor 40 includes: a core 43; and windings 41, 42 which are connected at one end to respective output ends of the PWM control bridges 20, 30 while being coupled with each other via the core 43. The windings 41, 42 are respectively wound in such directions that magnetic fluxes generated in the core 43 cancel each other out.

Abstract: According to an aspect of this disclosure, a circuit includes a voltage source and an output load, first and second resonant modules disposed between the voltage source and the output load, and first and second transformers. The circuit is further arranged such that the first transformer is disposed between the first resonant module and the output load, and the second transformer is disposed between the second resonant module and the output load. The circuit also includes a plurality of half-bridges coupled between the first and second resonant modules and the voltage source. The circuit further includes a voltage divider disposed between the voltage source and the plurality of half-bridges.

Abstract: Disclosed is a solid state power controller configured to supply electric power from an AC power supply to at least one load via at least one power distribution channel, the at least one power distribution channel comprising a primary solid state switching device and a secondary solid state solid state switching device connected in series. The solid state power controller includes a primary control terminal driver configured to supply a primary control voltage to the control terminal (G) of the primary solid state switching device with respect to a reference potential (R) and a secondary control terminal driver configured to supply a secondary control voltage to the control terminal (G) of the secondary solid state switching device.

Abstract: A resonant converter, including: a primary side circuit including at least one set of primary side switches, where the primary side circuit is configured to receive an input voltage; a resonant network coupled to the primary side circuit; a transformer having a primary side winding and a secondary side winding, where the primary side winding is coupled to the resonant network; a secondary side circuit including at least one set of secondary side switches, where the secondary side circuit is coupled to the secondary side winding of the transformer; and a control block that controls the secondary side switches according to the input voltage, the output voltage and the current detection signal, so that the secondary side winding of the transformer is short-circuited during a preset time interval before operating state of the primary side switches changes.

Abstract: A latch circuit includes first and second NAND circuits and first and second capacitive elements. The first NAND circuit has a first input node into which a first signal is input. The second NAND circuit has a first input node into which a second signal is input, a second input node which is connected to an output node of the first NAND circuit, and an output node which is connected to a second input node of the first NAND circuit. The first capacitive element has one end connected to the first input node of the first NAND circuit and has another end connected to the output node of the first NAND circuit. The second capacitive element has one end connected to the first input node of the second NAND circuit and has another end connected to the output node of the second NAND circuit.

Abstract: A single active bridge converter is provided. The single active bridge converter includes a transformer including a primary winding and a secondary winding, a primary side circuit electrically coupled to the primary winding and including an H bridge circuit, and a secondary side circuit electrically coupled to the secondary winding, the secondary side circuit including a switch configured to selectively short the transformer secondary winding.

Abstract: A method for semiconductor devices on a substrate includes using gate structures which serve as active gate structures in a MOSFET region, as dummy gate structures in a JFET region of the device. The dummy gate electrodes are used as masks and determine the spacing between gate regions and source/drain regions, the width of the gate regions, and the spacing between adjacent gate regions according to some embodiments, thereby forming an accurately dimensioned transistor channel.

Abstract: A controller includes a first control circuit coupled to an input side of a power converter. The first control circuit includes a timing and delay circuit and a switch selection circuit. A second control circuit is coupled to an output side of the power converter. The second control circuit includes a valley detection circuit and a synchronous rectifier control circuit. A third control circuit is coupled to the input side of the power converter. The third control circuit is coupled to drive an auxiliary switch coupled to an input side of an energy transfer element. The first control circuit is coupled to alternately drive a main switch, which is coupled to the input side of the energy transfer element, and the auxiliary switch in response to a command signal to transfer energy from the input side to the output side of the energy transfer element to drive a load.

Abstract: Described examples include a method of controlling a power converter including executing a plurality of cycles. Each cycle includes turning on a first switch during a first period, the first switch coupled between a power supply and an output inductance; turning on a second switch during a second period, the second switch coupled between an output inductance and ground; turning on a third switch at a first time during the second period, the third switch coupled between the power supply and an auxiliary inductance; and turning on a fourth switch on at a third time after the second time, the fourth switch coupled the auxiliary inductance and ground. The second period ends at a third time period after the first time based on a later of an overlap time and a current through a switch connected to the second switch current handling terminal exceeding a threshold current.

Abstract: The present invention provides a power supply for an inductive power transfer (IPT) system, comprising a current-fed push-pull resonant converter comprising a parallel-tuned resonant tank and a pair of switches enabling selective shorting of the resonant tank; and a controller adapted to control a shorting period of the resonant converter by selectively operating the switches. Methods for controlling an IPT power supply are also disclosed. The power supply may be controlled to regulate the output of an IPT pick-up inductively coupled with the power supply in use, or to operate at a zero voltage switching (ZVS) frequency.

Abstract: In order to enable a switching process with a zero-voltage sequence (ZVS) in a full bridge DC/DC converter (1) with phase shift control without having to provide an additional inductor for this purpose, it is provided that a short-circuit is generated in the secondary-side output rectifier (5) in the transition phase from the active to the passive phase prior to switching to a passive phase of the full bridge (2), said short-cut increasing the primary current (ip) across the primary side of the transformer (T) by means of the resulting short-circuit current (ik) across the secondary side of the transformer.

Abstract: A power supply circuit includes a pre-regulator configured to receive an input voltage and to generate an output voltage, and a switching current regulator coupled to an output of the pre-regulator and configured to regulate a level of current supplied to an output load. The switching current regulator is controlled by a switching signal having a duty cycle. The circuit further includes a controller that generates the switching signal. The controller monitors the duty cycle of the switching signal and controls a level of the output voltage generated by the pre-regulator by providing a control signal in response to the duty cycle of the switching signal.

Abstract: A resonant inverter includes first and second switches, first and second capacitive elements, a first coil, a second coil, a third coil, and a third capacitive element. The first and second switches are alternately turned on and off. The first and second capacitive elements are connected in parallel to the first switch and the second switch, respectively. The first coil is disposed between the first switch and an input voltage terminal. The second coil is disposed between the second switch and the input voltage terminal. The third coil and a third capacitive element are connected in series to each other and connected in parallel to a series circuit of the first and second coils. The first and second capacitive elements and the first and second coils constitute a plurality of first resonant circuits. The third coil and the third capacitive element constitute a single second resonant circuit.

Abstract: A hybrid transformer is provided that includes an electromagnetic transformer and an AC-AC converter with a DC bridge. The AC-AC converter is operable to keep the input voltage and current of the hybrid transformer substantially in phase and to reduce fluctuation in the output voltage of the hybrid transformer in the event of an increase or decrease in the input voltage.

Abstract: A flux converter for converting an input-side alternating current into an output-side DC current, wherein a power factor correction is provided and the flux converter comprises a transformer having at least two serially arranged primary windings and a secondary winding wound in same direction. In addition, a first switch is used to switch a storage capacitor in series with a first primary winding to the alternating current in a clocked manner via rectification elements and a second primary winding can be switched to the storage capacitor in a clocked manner by a second switch.

Abstract: A switched mode power supply comprising a switched mode converter and a controller for controlling the switched mode converter, the switched mode converter being provided for converting an input voltage to an output voltage and including, on a primary side, a primary winding and a controllable switch based circuitry connecting the input voltage over the primary winding; and, on a secondary side, a secondary winding coupled to the primary winding and a capacitive element connected over the secondary winding, wherein the output voltage is obtained as the voltage over the capacitive element.

Abstract: An apparatus and a method for generating a pulse width modulated, PWM, voltage doubler signal is presented The apparatus comprises a voltage source, a capacitor, an output node, a switchable circuit assembly for connecting the voltage source, the capacitor and the output node, and a controller for the switchable circuit assembly which is adapted to be switchable between a first circuit configuration in which the capacitor is connected in parallel to the voltage source so as to be chargeable by the voltage source, and a second circuit configuration in which the capacitor is connected in series between the voltage source and the output node, and wherein the control means is adapted to control the switchable circuit assembly to switch to the first circuit configuration in the first period, and to switch to the second circuit configuration in the second period.

Abstract: An electrical circuit includes a first circuit part and a second circuit part. A first electrical potential is applicable to the first circuit part, wherein a second electrical potential is applicable to the second circuit part. The two circuit parts are galvanically isolated from each other by an insulator, wherein the insulator includes a conducting portion. This conducting portion can be safely sensed by an additional circuitry, to detect if a full or partial contact to the first electrical potential or the second electrical potential has occurred due to a voltage shift or a current flow on the conducting portion, which is itself insulated. This sensing circuitry can incorporate protection elements to clamp voltages and limit currents to prevent destruction of connected circuitries in case of a fail of the insulation.

Abstract: A resonant converter includes a primary switching circuit having a primary winding and a primary switching stage configured to drive the primary winding; a secondary resonant circuit having a secondary winding magnetically coupled to the primary winding, a resonance capacitor connected in parallel to the secondary winding, and first and second secondary inductors respectively coupled between an output terminal of the converter and respective terminals of the resonance capacitor; a rectification stage connected in parallel with the resonance capacitor, and having first and second switches coupled to form a half-bridge; and a feedback command circuit. The command circuit is configured to receive feedback signals representing an output voltage and an output current at the output terminal of the resonant converter, receive voltages at the terminals of the resonance capacitor, and turn on/off, independently with respect to each other, the switches of the rectification stage and the primary switching stage.

Abstract: An apparatus for obtaining information enabling a characteristic like determination of maximum power point of a power source, the apparatus including at least an inductor and a capacitor, the information enabling the determination of the characteristic of the power source being obtained by monitoring the voltage charge of the capacitor, and a mechanism discharging the capacitor through the inductor prior to the monitoring of the charge of the capacitor.

Abstract: A driver circuit for powering a load is disclosed. The driver circuit includes a self-oscillating half-bridge circuit, a resonant driver in electrical communication with the self-oscillating half-bridge circuit, and a DC voltage supply in electrical communication with the resonant driver. The self-oscillating half-bridge circuit is configured to generate a high-frequency AC signal. The resonant driver is configured to limit a current of the high-frequency AC signal and produce a limited output voltage based on the high-frequency AC signal. The DC voltage supply is configured to rectify the limited output voltage into a DC output voltage including a substantially constant current for powering the load.

Abstract: A quasi-resonant device for a switching power, a quasi-resonant system for a switching power, and a method for a quasi-resonant control of a switching power are provided. The quasi-resonant device includes: a degaussing time sampling module, configured to sample a degaussing time Tds of a secondary coil of the transformer according to a feedback signal output by the switching power after the switching tube is turned off; a valley sampling module, configured to sample a resonant valley signal of the quasi-resonant module according to the feedback signal; a time producing module, configured to produce a time T with a predetermined ratio D by processing the degaussing time Tds; and a logic processing module, configured to obtain a first valley signal after the time T, and the first valley signal works as a switching signal T? to turn on the switching tube.

Abstract: A power supply circuit can be used to provide an alternating-current supply voltage to an electric motor. The power supply circuit is supplied by line power. The power supply circuit includes a inverter including at least one pair of transistor for generating a corresponding phase of the plurality of power supply phases. The inverter includes a transistor control circuit for switching the low-side transistor to its conducting state and the high-side transistor to its non-conducting state in case an excess voltage is detected at the input of the inverter.

Abstract: Disclosed are light-emitting diode (LED) driver circuits, methods, and a switch mode power supply. In one embodiment, an LED driver can include: (i) a silicon-controlled rectifier (SCR) and a rectifier bridge configured to receive an AC voltage, and to generate a phase-loss half sine wave voltage signal; (ii) a threshold voltage control circuit configured to receive a threshold voltage and an input voltage signal that represents the phase-loss half sine wave voltage signal, and to determine whether to output the threshold voltage based on angle information of the input voltage signal; (iii) a first control circuit configured to compare the input voltage signal against the threshold voltage output by the threshold voltage control circuit, and to generate a first control signal; and (iv) a power switch controllable by the first control signal to be off until an absolute value of the AC voltage is reduced to zero.

Abstract: Methods and apparatuses for programming a parameter value in an IC (e.g., any power electronic device, such as a controller of a power converter) are disclosed. The parameter can be selected/programmed by selecting a clamp using an external optional (selectively inserted) diode coupled to a multi-function programming terminal. In particular, a controller IC for a power converter can be externally programmed via one or more multiple function terminals during startup of the converter to select between two or more options using the external programming terminal(s). Once programming is complete, internal programming circuitry may be decoupled from the programming terminal and during normal operation the programming terminal may then be used for another function, such as a bypass (BP) terminal to provide a supply voltage to the IC or other required functionalities.

Abstract: A grid tied inverter connectable to an electricity grid having a DC to DC current fed push-pull inverter to generate a current waveform from a DC voltage source. The push-pull inverter includes a transformer having a first side winding connectable to a battery and a second side winding connectable to the grid. The first end of the second side winding is connected between two diodes connected in series between a positive and negative output rail and being oriented in the same direction. The second end of the second side winding is connected between two capacitors connected in series between the positive and negative output rail. A further winding is connected at one end between the two capacitors and at its other end between another two diodes connected in series between the positive and negative output rail.

Abstract: A solar module has a solar cell which generates a DC voltage. The module has a converter for converting a DC voltage fed into its input. The module contains a semiconductor switch and a controller which drives a switching input of the semiconductor switch. The controller drives the semiconductor switch variably so that the semiconductor switch switches more slowly during the transition operation than during normal operation, thereby reducing a dynamic overvoltage on the switch such that the voltage present on the switch does not exceed the blocking voltage of the switch.

Abstract: A dual resonance circuit is formed of two transformers, two resonance inductors and two resonance capacitors for a resonance type switching power supply employing parallel connected transformers. The secondary winding of the transformer is configured in a center tap structure, and a top and bottom symmetrical voltage multiplying rectifier is connected to the secondary winding coupled with the parallel connected transformers, thereby obtaining the same effect as when one transformer is used. The present invention achieves a low loss in the typical resonance type half bridge power supply even though two transformers are employed, and the switching power supply with a lowered height and thinned structure can be provided with the aid of the optimized arrangements of the resonance devices. The internal power loss can be lowered by using two parallel connected transformers as compared to a resonance type switching power supply which employs one transformer.

Abstract: A method for operating the DC-to-DC voltage regulator including plural active switches and plural inductors is disclosed. The method including the steps of: turning on the first active switch, and then turning off the first active switch when the current flowing in the first inductor is equal to zero; turning on the third active switch, and then turning off the third active switch when the current flowing in the second inductor is equal to zero; turning on the second active switch, and then turning off the second active switch when the current flowing in the first inductor is equal to zero; and turning on the fourth active switch, and then turning off the fourth active switch when the current flowing in the second inductor is equal to zero.

Abstract: A filter device (10) for filtering high-frequency interferences, such as due to switching flanks of a DC converter, has a current path (4) between an input (2) and an output (3), and an inductor (L) in the current path (4), wherein the inductor (L) is disposed in the current path (4) as a first component and is connected to the input (2), and wherein a reverse polarity protective diode (D) is disposed in series with the inductor (L) downstream thereto.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: A DC to DC converter system, includes inverter circuitry having a first and a second switch, the inverter circuitry further configured to generate a first and a second gate control signal, the signals configured to open and close the first and second switch, respectively, and generate an AC signal from a DC input signal. The system further includes transformer circuitry configured to transform the AC signal into a sinusoidal AC signal, second stage circuitry configured to rectify the sinusoidal AC signal to a DC output signal, and hybrid control circuitry configured to modulate the first and second gate control signals, wherein the modulation comprises pulse frequency modulation (PFM) and pulse width modulation (PWM).

Abstract: An energy recovery snubber circuit for use in switching power converters. The power converters may include a switch network coupled to a primary winding of an isolation transformer, and rectification circuitry coupled to a secondary winding of the isolation transformer. The energy recovery snubber circuit may include clamping circuitry that is operative to clamp voltage spikes and/or ringing at the rectification circuitry. The clamped voltages may be captured by an energy capture module, such as a capacitor. Further, the energy recovery snubber circuitry may include control circuitry operative to return the energy captured by the energy capture module to the input of the power converter. To maintain electrical isolation between a primary side and a secondary side of the isolation transformer, a second isolation transformer may be provided to return the captured energy back to the input of the power converter.

Abstract: This disclosure relates to a power conversion system to power a variable impedance load with a variable power source, the power conversion system comprising a power converter including input terminals adapted to receive variable power from the variable power source and output terminals providing a converted power to the variable impedance load based on the variable power received at the input terminals. The power converter increases the input voltage to an output voltage. The power converter is configured to reflect a source impedance of the variable power source to the variable impedance load.

Abstract: A voltage converter (10) comprises an input (11) for receiving an input voltage (VIN), a first output (12) for providing a first output voltage (VPOS) and a second output (13) for providing a second output voltage (VNEG). The first output voltage (VPOS) and the second output voltage (VNEG) have opposite polarities. A switching arrangement (14) of the voltage converter (10) is designed to provide energy to an inductor (15) in a charging phase (A) of operation and to provide energy from the inductor (15) to the first output (12) and, via a flying capacitor (16), to the second output (13) in a discharging phase of operation. The first duration (t1) of the charging phase (A) of operation is controlled such that the difference between a first predetermined value and the sum of the absolute value of the first output voltage (VPOS) and of the second output voltage (VNEG) is minimized.

Abstract: A power-supply unit including a transformer, a full bridge circuit having four arm switches on a primary side of the transformer, a rectifier and smoothing circuit including two synchronous rectifier switches on a secondary side of the transformer, a choke coil, and a capacitor, an output terminal in the rectifier and smoothing circuit, a control circuit controlling ON/OFF of the four arm switches of the full bridge circuit and the two synchronous rectifier switches of the rectifier and smoothing circuit, a resonant inductor including a leakage inductor component and a parasitic inductor component on the primary side of the transformer, and a resonant capacitor, and in which the control circuit includes a timing variable unit which varies switching timings of the two synchronous rectifier switches of the rectifier and smoothing circuit based on an output current flowing in the output terminal provided in the rectifier and smoothing circuit.