| 摘要 |
PURPOSE:To enable to perform a high speed switching by forming a control circuit of a switching transistor of two pulse width modulators to conduct the transistor by the first pulse and to interrupt the transistor by the second pulse. CONSTITUTION:The output of a rectifier 1 is controlled by turning a switching transistor 3 ON and OFF by a pulse from a control circuit 2, thereby obtaining a stabilized voltage at the secondary side of a transformer 4. At this time, the control circuit 2 is formed of two pulse width modulators 21, 22 for applying a common reference pulse to form a forward pulse by the first pulse and to form a reverse pulse by the second pulse set to the pulse width narrower than the first pulse, thereby controlling the transistor 3. Accordingly, the storage time of the transistor 3 can be effectively finished at the reverse pulse applying time, and high speed switching can be performed without using an expensive transistor. |
