DRIVE CIRCUIT FOR SYNCHRONOUS RECTIFICATION TYPE FORWARD CONVERTER

摘要

PROBLEM TO BE SOLVED: To provide a drive circuit for a synchronous rectification type forward converter which can turn on a rectifying semiconductor switch element for commutation always quickly.;SOLUTION: This drive circuit is equipped with a control circuit 2 which drives a main switch element 4, the rectifying semiconductor switch element 5 which lets a current flow via a main transformer 3 synchronously with the turning on/off of the main switch element 4, and a rectifying semiconductor switch element 6. One end of the sub winding 3c of the main transformer 3 is connected to the gate circuit of the rectifying switch element 6, and the other end is connected to the neutral point of a series circuit composed of an impedance element such as a diode 12, etc. and a capacitor 13. The anode of the diode 12 is connected to the terminal on the side where the dot of the secondary winding 3b of the main transformer 3 is affixed, and a cathode is connected to one end of a capacitor 13. The other end of the capacitor 13 is connected to the source of the rectifying semiconductor switch element 5.;COPYRIGHT: (C)2004,JPO