Power Supply Control Circuit, Power Supply Device and Electronic Apparatus

摘要

The present invention provides a power control circuit and a power device using the power control circuit, wherein quasi resonance is performed by the power control circuit using a coil, current flowing in the coil is monitored by a simple configuration, and a zero cross point or a bottom in resonance is detected. The present invention provides a power control circuit and a power device using the power control circuit. The power control circuit includes a detection circuit connected to a drain of MOSFET, the MOSFET serially connected between an inductor connected to an alternating-current wire and a current sensing resistor connected to ground potential; and a quasi resonance control circuit connected to the detection circuit and the MOSFET for performing quasi resonance control to inductor-current at a zero cross point or a bottom point in a time sequence of discharging while conducting the inductor-current of the inductor.

主权项

1. A power control circuit, comprising:
a high pass filter, connected to a drain of a MOSFET, wherein the MOSFET is serially connected between an inductor connected to an alternating-current wire and a current sensing resistor connected to a ground potential; and
a quasi resonance control circuit, connected to the high pass filter and the MOSFET, wherein when an inductor-current of the inductor is conducted in a dicharging time sequence, the quasi resonance control circuit performs quasi resonance control upon the inductor-current of the inductor at a zero crossing point or a bottom point in the dicharging time sequence based on an output of the high pass filter.