| 摘要 |
A residual current protection device comprises a leakage detection circuit, a trigger circuit M3 and a voltage stabilizing circuit M5 providing a stable supply voltage Vcc to the leakage detection circuit, the stabilization circuit M5 having a capacitor C2 for storing electrical energy and providing a voltage Vcc and a charging control circuit M51 that causes the power line L to charge the capacitor C2 when Vcc is equal to or less than a predetermined threshold and stops the charging when Vcc exceeds the threshold. The charging control circuit M51 may comprise a controlled switch Q1 in series with the capacitor C2 and a voltage clamping element D5, wherein the switch Q1 is turned on when the voltage difference between the clamping element D5 and the capacitor C2 exceeds its turn-on voltage. The switch Q1 may be a MOS transistor and the clamping element D5 may be a zener diode, the cathode of which may be connected to the gate of the switch Q1. The turn-on voltage of the clamping element D5 may be higher than that of the switch Q1. |
