摘要 |
An AC-DC converter is disclosed. The AC-DC converter includes an OFF-time clamping circuit. The OFF time clamping circuit outputs a triggering signal when a main switch circuit of the AC-DC converter is switched from ON state to OFF state. When an input AC voltage is too small, and a terminal voltage at a first current-conducting terminal of the main switch circuit of the AC-DC converter is lower than a specific voltage such that a switching control circuit can not turn on the main switch circuit again, the switching control circuit can still turn on the main switch circuit again by the triggering signal. Therefore, the OFF time of the main switch circuit is clamped. The switching control circuit can control the switching operation of the main switch circuit. |