| 摘要 |
PROBLEM TO BE SOLVED: To prevent false firing of an insulated gate semiconductor device by providing a series circuit, consisting of a capacitor and a semiconductor switch between the gate terminal and the emitter terminal of the insulated gate semiconductor device, and turning the semiconductor switch of the series circuit on, only for a specified time during the negative period of a gate control signal. SOLUTION: In a gate control circuit for an insulated gate semiconductor device 11, which supplies on/off control signals to a gate G of the semiconductor device 11 via a gate resistor 15 by the use of semiconductor switches SW1, SW2, a series circuit of a capacitor 17 and a semiconductor switch SW3 are formed between the gate G and an emitter E. The semiconductor switch SW3 is controlled by a switching control circuit 23 via a drive circuit 16. The semiconductor device 11 is prevented from being turned on by malfunctioning, by turning the semiconductor switch SW3 on only for a prescribed time during a period, during which a gate signal for making the semiconductor device 11 in an off- state is controlled to be negative.
|
