The present disclosure discloses a zero-crossing detection circuit, including: a zero-crossing judgment module, having a first end and a second end, wherein the first end is connected to a power supply and the second end is grounded; a photoelectric coupler, connected to the zero-crossing judgment module; an optocoupler driving module, connected to the photoelectric coupler; and an energy storage capacitor, wherein the energy storage capacitor is configured to provide excitation power for the photoelectric coupler and the optocoupler driving module.

A controller protection circuit for a voltage power optimiser. The circuit having: a first terminal for connecting to a first end of a winding in the voltage power optimiser; a second terminal for connecting to a second end of the winding in the voltage power optimiser; and a thyristor. The controller protection circuit also includes a thyristor gate control circuit. The thyristor gate control circuit is configured to: set the gate control signal such that the thyristor is configured to conduct in response to a potential difference between the anode terminal and the cathode terminal of the thyristor; and set the gate control signal such that the thyristor is configured not to conduct in response to a signal received from a voltage controller. The thyristor gate control circuit includes a normally-on switch having a conduction channel and a control terminal, and a photovoltaic isolator configured to set the gate control signal such that the thyristor is configured not to conduct in response to a signal received from a voltage controller.

In a DC/DC converter, a first switching circuit is connected between a first winding of a transformer and a DC power supply, and a second switching circuit is connected between a second winding and a battery. In charging the battery, a control circuit controls a phase shift amount of a first diagonal element in the first switching circuit and a phase shift amount of a second diagonal element in the second switching circuit relative to the drive phase of a first reference element in the first switching circuit. During a step-up charge control period, if charge current is positive or zero, the control circuit performs control so that the phase shift amount becomes greater than the phase shift amount by an amount exceeding a short-circuit prevention time for the semiconductor switching elements. Thus, step-up operation is prevented from becoming unable to be performed due to the short-circuit prevention time.

A method for controlling an output of an electrical AC voltage U comprising the following steps: switching on a current flow I induced by the AC voltage as soon as an absolute value of the AC voltage U exceeds a switching-off target voltage, and switching on the current flow I as soon as the absolute value for the AC voltage U falls below a switching on target voltage. The switching-off target voltage and the switching-on target voltage are defined as positive and the switching-on target voltage is lower than or equal to the switching-off target voltage. The method according to the invention serves to dim an LED lamp in a brightness range of 0% to 100% of a maximum brightness of the LED lamp.

An insulated power supply apparatus includes, a transformer; a switching element connected in series with a primary side winding of the transformer; an active clamp circuit connected between terminals of the primary side winding of the transformer; and a power supply control semiconductor device. The switching element includes a field effect transistor and a current-voltage conversion element is connected between a source terminal of the switching element and a grounding point. The power supply control semiconductor device includes the following, a first external terminal in which voltage according to a drain side of the switching element is input, a second external terminal in which voltage converted by the current-voltage conversion element is input, an on/off control circuit that performs turn-on and turn-off of the switching element, and a ZVS determining circuit that determines whether zero voltage switching control is performed.

A control circuit for a switched-mode power converter to generate a control signal for controlling switching transistors in the power converter is disclosed. The control circuit includes: a comparator; a ramp compensation circuit for producing and applying a ramp compensation signal to a first or second input of the comparator; an on-time generation circuit to generate an on-time timer signal; and a control signal generation circuit to generate, based on the comparison signal and the on-time timer signal, the control signal for controlling the switching transistors in the power converter. The ramp compensation signal output from the ramp compensation circuit is configured with: a first slope during an inductor demagnetization interval in operation of the power converter in CCM and a second slope during an inductor demagnetization interval and a zero-current interval in operation of the power converter in DCM, the first slope is greater than the second slope.

A three phase regulator rectifier for automotive battery charging applications of a two wheeled vehicle having a few discrete components and providing programmable feedback control for improved efficiency in battery charging applications.

A circuit breaker includes an electromechanical switch, a current sensor, a voltage sensor, and a processor. The electromechanical switch is serially connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-closed state or a switched-open state. The current sensor is configured to sense a magnitude of current flowing in a path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage at a point on the path between the line input and load output terminals and generate a voltage sense signal. The processor is configured to receive and process the current sense signal and the voltage sense signal to determine operational status information of the circuit breaker and determine power usage information of a load connected to the load output terminal.

The present invention addresses the problem of detecting the timing at which an inductor current becomes zero, turning on a switching element at the optimal timing, and enhancing power efficiency without increasing part quantity or external terminal quantity. A control circuit is configured from a semiconductor integrated circuit; is provided with a first external terminal to which a voltage produced by the conversion of the current flowing through a switching element by a current-to-voltage conversion element is input, a second external terminal to which the voltage of a point of contact of an inductor and rectification element or a voltage proportional thereto is input, a filter for smoothing the voltage input into the second external terminal, and a voltage comparison circuit for comparing the voltage smoothed by the filter and the voltage input into the second external terminal; and performs control such that the switching element is switched from off to on near the point where the inductor current becomes zero on the basis of the voltage comparison circuit output and the switching element is switched from on to off in response to the voltage applied to the first external terminal reaching a prescribed voltage.

A power converter circuit (300) comprising: a full bridge inverter and an resonance circuit and a control circuit. The full bridge comprises a first leg (HBx) and a second leg (HBy), each leg having two switches and a switching node between the switches, the switches of the first leg being different from those of the second leg. The resonance circuit is connected between said switching nodes, and comprises an inductance (Lp) in series 5 with a capacitance (Cr). The control circuit generates control signals for the switches in accordance with a predefined scheme having two energizing phases (φ1, φ3) and two passive conducting phases (φ2, φ4) with a configurable duty cycle (DC1, DC2) for achieving zero-voltage-switching (ZVS).