| 摘要 |
A two-terminal self-powered synchronous rectifier (ASR) is provided, together with two-terminal or three-terminal packaged devices that can replace an output diode rectifier (D) in a switched mode power supply. The synchronous rectifier comprises a field-effect transistor (M) having its source-drain path in a first arm (11) between the two rectifier terminals (A,K), normally a parallel diode (BD) in a second arm (12), a gate-control circuit (GC) connected to a gate electrode (g) of the transistor (M) for switching the transistor (M) synchronously on and off in accordance with voltage reversal at the two rectifier terminals (A,K), and a charge pump (C,R; C,R,C2,R2) in a third parallel arm for powering the control circuit from the power signal being rectified by the rectifier. |
