超高オフゲート利得GTOサイリスタ

抄録

A new class of thyristor action is proposed for switching off currents with very small off-gate current. The new units exceed conventional GTO thyristors by _??_100times in off-gate gain. The unit consists of a main pnp-transistor, a control npn-transistor, a diode and a resistor. The two transistors form conventional thyristor equivalently. The control transistor has a bypass diode between its base resistor and emitter, to make base current very small in order to be absorbed with small off-gate current. The bypass diode puts away the restraint on amplitude factors of inner transistors, in contrast to conventional GTOs. The base resistor, deciding bypass ratio, frees transistor from deeply saturated states and realizes high speed actions. And also, the base resistor restricts inflow into off-gate from main current.