| 摘要 |
PURPOSE:To avoid the commutation failure and also to cope with the high frequency of a horizontal deflecting circuit, by giving the ON/OFF control to a GTO (gate turn-off) thyristor with a flyback pulse corresponding to the reference voltage and the horizontal deflection control circuit. CONSTITUTION:The ON control is given to a GTO thyristor GTO12 in response to the output voltage and a flyback pulse together with the OFF control carried out in response to the output pulse of a horizontal deflection control circuit 42. Thus the GTO12 can be turned off regardless of the output of a flyback transformer 34. This avoids the commutation failure. Furthermore a high-speed switching action is possible owing to the use of the GTO12. Then an easy countermeasure is also possible to the high frequency of the circuit 42. In addition, the reverse voltage produced when the GTO12 is turned off is prevented by a diode 11. This can suppress the turn-off loss of the GTO12. |
