A rectifying circuit (10, 10.1, 10.2, 10.3, 10.4, 10.5, 10.6) comprising a first circuit branch (20) and a second circuit branch (30) in parallel between an output node (Out) and a reference node (GND), each circuit branch (20, 30) comprising an inductive element (L1, L2) in series with an electric current controlling element (23, 33) and an input node (In1, In2) arranged between the inductive element (L1, L2) and the electric current controlling element (23, 33), a voltage that is variable over time being applied between the input nodes (In1, In2) during the operation of the rectifying circuit.

A system and method for high speed switching comprises receiving voltage inputs at a bridge rectifier, generating a control signal from a transistor, and driving a gate of a field effect transistor (FET) via the control signal of the transistor, wherein a source of the FET is connected to a negative output of the bridge rectifier and a drain of the FET is connected to a positive output of the bridge rectifier through a load. The system and method further comprises limiting current flowing to the gate of the FET through first and second resistors and first and second diodes connecting the voltage inputs to the gate of the FET and limiting voltage to the gate of the FET below a maximum voltage rating of the FET by a Zener diode connected to the gate of the FET.

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.

A voltage-regulating circuit comprising: a voltage regulator, a switch, a first comparing circuit for comparing the amplitude deviation between the input voltage and the output voltage to a first threshold, a second comparing circuit for comparing the amplitude of the output voltage to a second threshold, and a control circuit for commanding the switch to open or close depending on the comparisons made by the first comparing circuit and by the second comparing circuit.

Also disclosed is a regulated power-supply module comprising such a voltage-regulating circuit.

In response to a problem wherein a voltage of a capacitor of a power conversion device decreases when a voltage of an alternating current power supply is restored after once decreasing, the voltage of the capacitor drops below a maximum value of the voltage of the alternating current power supply when power is restored, and an inrush current occurs, the power conversion device, provided between an alternating current power supply and a load, is such that a decrease in an input voltage or an input current of a power converting unit is detected, a change in the voltage of the capacitor is predicted, and operations of the power converting unit are caused to stop before the voltage of the capacitor drops to or below the maximum value of the voltage of the alternating current power supply, thereby restricting an occurrence of an inrush current.

A voltage converter circuit, comprising: a bridge rectifier; a first transistor, having a first end, a second end and a third end; a second transistor, having a first end and a second end; wherein the first end of the first transistor and the first end of second transistor are electrically connected to bridge rectifier, and the second end of the first transistor is electrically connected to the first end of the second transistor; and a Zener diode, connected between the third end of the first transistor and the second end of the second transistor.

The present application provides a power converter and a power supply system, the power converter includes: a star/delta switching unit, a first power conversion unit, a second power conversion unit, a third power conversion unit, and a controller; AC terminals of the first power conversion unit, the second power conversion unit and the third power conversion unit are connected to a three-phase AC terminal through the star/delta switching unit, and DC terminals of the first power conversion unit, the second power conversion unit, and the third power conversion unit are connected to a DC power terminal; wherein the controller is configured to control the star/delta switching unit according to a signal reflecting a voltage of the DC power terminal, to form a star connection or a delta connection among the three-phase AC terminal and the first power conversion unit, the second power conversion unit and the third power conversion unit.

A method involves determining a target number of valleys of a resonant waveform at a drain node of a main switch of a power converter. The target number of valleys corresponds to a desired off-time of the main switch. A first intermediate valley number of a series of intermediate valley numbers is selected. An average of the series of intermediate valley numbers corresponds to the target number of valleys. A first average off-time of the main switch is controlled, for a duration of a first modulation period, such that the first average off-time corresponds to the first intermediate valley number. Upon expiration of the first modulation period, a second intermediate valley number of the intermediate valley numbers is selected. A second average off-time of the main switch is controlled, for a duration of a second modulation period, such that the second average off-time corresponds to the second intermediate valley number.

A switching power supply (switched-mode power device) includes a rectifier for a mains connection and for rectifying a three-phase AC voltage, a first converter and a second converter, the input voltage of which forms an intermediate circuit voltage, where the first converter regulates the intermediate circuit voltage such that the voltage substantially corresponds to a predefinable output voltage of the second converter multiplied by a load-independent transformation ratio on operation of the second converter with a resonant frequency, where upon forced reduction of the output voltage from the second converter, the first converter can set an, on average, sufficiently low intermediate circuit voltage such that the second converter can be operated substantially with the resonant frequency for a load-independent transformation ratio, where a signal for closed-loop control of the first converter stage can be derived from voltage and/or current information from the second converter.

A method for high speed switching comprises receiving voltage inputs at a bridge rectifier, receiving a logic input signal at an optical isolator and generating an output signal from the optical isolator based on the logic input signal, and driving a gate of a field effect transistor (FET) via the output signal of the optical isolator, wherein a source of the FET is connected to a negative output of the bridge rectifier and a drain of the FET is connected to a positive output of the bridge rectifier through a load. The method further includes limiting current flowing to the gate of the FET through first and second resistors and first and second diodes connecting the voltage inputs to the gate of the FET and limiting voltage to the gate of the FET below a maximum voltage rating of the FET by a Zener diode connected to the gate of the FET.