Hello.i have a full wave rectifier followed by a capacitor and a led in series with a resistor.When i power off the circuit the led slowly turns off due to the capacitors charge.How to make it turn off immediately at the moment i remove the ac power? i dont mind using extra circuit.
Do you want the capacitor to discharge too or just the LED? As an engineer who has to touch high voltage circuits I like LED's that are on until there is truly no power.
Either move your LED onto its own source without any C or make an AC detection circuit that disables the LED.
A capacitively coupled solution may be good in either case.
Or:
and put a series blocking diode between the rectifier and the bulk capacitor. Wire your LED right after the bridge rectifier, but BEFORE the bulk capacitor.
and put a series blocking diode between the rectifier and the bulk capacitor. Wire your LED right after the bridge rectifier, but BEFORE the bulk capacitor.