Patent ID: 7586764

Claim:
A rectifier filter control device for a power supply, comprising: a control circuit of a power supply connected to a logic IC, which is used to actuate at least more than one actuating IC; a connecting terminal of a rectifier filter circuit respectively connects to a saturable inductor, a diode and a capacitor; a first electronic switch connected between positive and negative electrodes of a first rectifier of the rectifier filter circuit; a second electronic switch connected between positive and negative electrodes of a second rectifier of the rectifier filter circuit; wherein an actuating IC is used to control on/off states of the second electronic switch, and another actuating IC is used to control on/off states of the first electronic switch; whereby a voltage difference is formed between two terminals of the saturable inductor when a reverse current flow flows back to the saturable inductor of the rectifier filter circuit, thereby causing a contact point of the saturable inductor to generate a counter electromotive force that places the diode in a conducting state, and a zero voltage potential is formed at signal input terminals of the actuating ICs, thus, the actuating ICs do not output signals to the first and second electronic switches, which thus assume off states thereby preventing reverse current flow from burning out the two electronic switches.