An auxiliary supply for a switched mode power supply, which includes at least a transformer with a primary side and a secondary side, wherein the auxiliary supply provides a power supply to units arranged on the secondary side of the switched mode power supply independently of an operating state of the switched mode power supply, where the auxiliary supply in this case, on the primary side, which corresponds to the primary side of the switched mode power supply, has a frequency generator for generating an ac voltage with a predetermined frequency, where on the secondary side, which corresponds to the secondary side of the switched mode power supply, the auxiliary supply has a rectifier unit for a secondary side supply current and/or a secondary side supply voltage, and where a galvanic separation unit, which is particularly formed by two capacitors, is provided between the primary side and the secondary side.

An exemplary method of receiving wireless power from a wireless power transmitter includes, at a wireless power receiver having a controller, an antenna, a rectifier coupled with the antenna, and a boost converter coupled with the rectifier: (i) rectifying, by the rectifier, energy from wireless power transmission waves received by the antenna into a first voltage, (ii) increasing, by the boost converter, the first voltage to a second voltage based on instructions from the controller, and (iii) controlling, by the controller, an amount of increase in voltage from the first voltage to the second voltage based on a comparison.

An uninterruptible power supply circuit is provided. The uninterruptible power supply circuit includes a first diode, a second diode, a bridge rectifier, and one or more electrical loads. The first diode, the second diode, the bridge rectifier, and the one or more electrical loads are electrically connected in the uninterruptible power supply circuit to drive the one or more electrical loads with a DC voltage or the intended AC supply voltage when the AC supply voltage is cutoff.

A device comprises a gate drive bridge coupled between a bias voltage of a power converter and ground and a transformer connected to the gate drive bridge, wherein the transformer comprises a primary winding connected to two legs of the gate drive bridge respectively and a plurality of secondary windings configured to generate gate drive signals for low side switches, high side switches and secondary switches of the power converter.

The invention relates to photoluminescent signs, in particular to signs in which one or more light emitting diodes (LEDs) emit light that excites one or more photoluminescent (PL) elements. In one aspect, a sign may include one or more photoluminescent elements: one or more light emitting diodes (LEDs) arranged to excite the one or more photoluminescent elements; and circuitry arranged for connection to an AC power supply and supplying power to the LEDs.

Provided is a pre-charge circuit and a photovoltaic inverter. The pre-charge circuit includes an alternating current power source, a half-bridge rectifier, an auxiliary charging capacitor, a current limiting device and a controllable switch. The pre-charge circuit is connected to a target charging capacitor to form a voltage doubling rectifier circuit. A direct current side of the half-bridge rectifier is connected in parallel to the target charging capacitor, and an alternating current side of the half-bridge rectifier is connected to one end of the alternating current power source. One end of the auxiliary charging capacitor is connected to any one end of the target charging capacitor, and the other end of the auxiliary charging capacitor is connected to the other end of the alternating current power source.

For defining an electric potential of input lines of an inverter with respect to ground, in all current-carrying output lines of the inverter capacitors are arranged and charged to a DC voltage in order to shift the electric potential of the input lines with respect to a reference potential present at the current-carrying output lines of the inverter by this DC voltage.

The invention relates to an operating device (1) for lighting means (8), having a circuit (101) for dividing a rectified alternating voltage to direct voltages of lower levels, wherein the circuit (101) comprises a PFC block comprising a plurality of half bridge converters (102, 103, 104) that are arranged such that the sum of the input voltage drops across the half bridge converters (102, 103, 104) corresponds to the value of the rectified alternating voltage, wherein the circuit (101) is the first active stage in a power supply for the lighting means (8).

An electric household appliance (1) has an electronic control unit (5) powered by a low-voltage power unit (6), and a device (7) for reducing energy consumption of the electric household appliance in standby mode. The device includes: a bistable relay (21) which is switched by a low-voltage enabling signal (S2) to a closed position to turn on the low-voltage power unit (6), or is switched by a disabling signal (S3) to an open position to turn off the low-voltage power unit (6); a low-voltage capacitive power unit (10) designed to generate the low-voltage enabling signal (S2); and a hand-operated control device (11) interposed between the low-voltage capacitive power unit (10) and the bistable relay (21) to supply the low-voltage enabling signal (S2) to the bistable relay.

A method comprises providing a resonant converter comprising a switching network comprising a first high-side switch, a second high-side switch, a first low-side switch and a second low-side switch, a resonant tank coupled between the switching network and a transformer and a rectifier coupled to a secondary side of the transformer, coupling a driver to the switching network and the rectifier, wherein the driver includes a first winding coupled to the rectifier, a second winding coupled to the first high-side switch and a third winding coupled to the second high-side switch, detecting a signal indicating a soft switching process of the driver and adjusting a resonant frequency of the driver until the resonant frequency of the driver approximately matches a switch frequency of the resonant converter.