PURPOSE:To decrease an ON-state voltage, to widen a safe operating area, and to realize fast switching by providing the bypass of a gate current for turn-on between the base and the emitter of a transistor. CONSTITUTION:When the gate current for turn on is permitted to flow by using a gate circuit 3, the current flows in the gate terminal 8 of an arc- suppressing switching device 1, and flows out from the cathode terminal of the device 1, and returns to the circuit 3 bypassing a resistor 4 or a diode 5. Thereby, the device 1 is turned on, and it is possible to permit the current to flow on a load connected to a power source to be connected to an anode terminal 6 and the cathode terminal 7. Next, when the gate current for turning off the device 1 is permitted to flow from a terminal 8, a reverse bypass is formed between the gate and the cathode, and a depletion layer is formed, then, the device 1 is turned off. As a result, the transistor 2 is turned off, and no load current flows.
展开▼
