GATE DRIVE CIRCUIT FOR GATE TURN-OFF THYRISTOR

摘要

PURPOSE:To prevent the erroneous operation of a GTO due to a noise by providing a noise signal cancelling circuit having a time constant longer than the pulse width of a noise signal. CONSTITUTION:The gate drive circuit of a GTO is constructed to have a DC insulating circuit 1, a waveform shaper 2 and a waveform control circuit 3, and to alternately apply ON and OFF signals obtained from the circuit 3 to transistors Q1, Q2 of the prescribed circuit configuration connected to the gate of a GTO4. A noise signal cacelling circuit 5 to obtain a synthesized output by coupling a monostable multivibrator to an AND circuit is inserted between the shaper 2 and the circuit 3. Since the circuit 5 has a time constant longer than the pulse width of the noise signal generated in the circuit, the erroneous operation of the GTO due to the noise can be prevented.