| 摘要 |
PURPOSE:To reduce the unnecessary power consumption as well as to prevent the external flowout of the signal by stabilizing the voltage via the switching action of the thyristor and also providing the half-wave rectifying circuit and the smoothing circuit at the front step of the thyristor. CONSTITUTION:The output terminal of rectifying/smoothing circuit 4 is connected to the anode of thyrestor 7, and smoothing circuit 8 is connected to the cathode of thyristor 7 respectively. In this case, trigger circuit 9 detects the fact that the voltage exists at the anode of thyristor 7 and no voltage exists at the cathode respectively, and the signal is delivered to the gate electrode of thyristor 7 to make the thyristor conduct. On the other hand, the flyback pulse obtained from flyback transformer 11 is supplied to the anode of 7 in the negative polarity to produce the pulse which varies its phase according to the output fluctuation of circuit 8 provided at the cathode side of 7. This pulse is then applied to the gate electrode of 7 with the positive polarity. As a result, the unnecessary power consumption can be decreased, and the unnecessary flowout of the signal can be prevented. |
