| 摘要 |
PURPOSE:To enable the high speed operation of a main transistor by flowing a sufficient reverse base current during the storage time of the main transistor. CONSTITUTION:When a drive transistor Q2 is turned OFF, a reverse voltage between the base and the emitter of a main transistor Q1 is induced in the second winding II of a drive transformer T2, and a reverse voltage between the base and the emitter of the transistor Q1 is induced in the fourth winding IV. Accordingly, a reverse base current is flowed through a resistor R1 by the reverse bias voltage induced in the winding II, and a sufficient reverse base current is flowed through a diode D3 by the winding IV having less number of turns as compared with the winding II. Thus, base storage charge can be abruptly discharged to shorten the storage time. |
