SYNCHRONOUS COMMUNICATION TYPE FORWARD CONVERTER

摘要

PROBLEM TO BE SOLVED: To provide a synchronous commutation type forward converter capable of preventing a secondary side switch element and a main switch element from being damaged. SOLUTION: The synchronous commutation type forward converter comprises a secondary auxiliary switch element Q5 having a drain and a source connected between the gate and the source of a communication switch Q3 so that the gate of the element Q5 is connected directly or via a resistor to the gate of the element Q2 to detect a rise in the voltage between the gate and the source of the communication switch element Q2 due to a decrease in the voltage between the gate and the source of the element Q3 so that the on-time of the element Q3 is limited by turning on the element Q5 to limit a self-excited oscillation frequency. COPYRIGHT: (C)2003,JPO