Patent ID: 6690143
Filing Date: 2004-02-10
Classification: G05F,H02M,Y02B,Y02P

Abstract:
A power factor correction (PFC) circuit with a snubber, comprising:an input part with two output terminals for receiving an AC voltage and outputting a first DC voltage; a main part for converting the first DC voltage to a second DC voltage, comprising a primary inductor with one terminal connected to one output terminal of the input part, a switch connected between the other terminal of the primary inductor and the other output terminal of the input part, a primary diode with an anode connected to the other terminal of the primary inductor, and an energy storage capacitor connected between a cathode of the primary diode and the other output terminal of the input part; and a snubber for ensuring the switch to operate in soft turn-on and soft turn-off, comprising a cascaded device with one terminal coupled to the output terminal of the input part which at least is composed of a first diode and a resonant inductor, a second diode connected between the other terminal of the cascaded device and the cathode of the primary diode, and a resonant capacitor connected between the anode of the second diode and the anode of the primary diode.