| 摘要 |
PURPOSE:To improve the noise resistance and to reduce the number of parts by biasing the gate of a gate turn-off thyristor (GTO) through a photosensitive element with a positive voltage, and emitting a trigger light pulse to the element. CONSTITUTION:The anode A2 of a GTO1 is biased through a load resistor 11 to VAK'12, and a photosensitive element 5 and a photosensitive element 6 for quenching a light are connected with the gate G4. The elements 5, 6 increase the conductivity by emitting a light, and are connected with positive and negative power sources Vt7, Vg8. Thus, when a trigger pulse LT9 is emitted to the element 5, it becomes low resistance state, the gate G4 is positively biased to turn the GTO1 ON. When a quenching light pulse LQ10 is emitted to the element 6 with the GTO1 being ON state, holes are removed from the gate G4 to turn the GTO1 OFF. |
