Electrical – LED bulb flicker @ rate of 50 Hz or more


I am currently testing a 5W LED bulb (direct operating on 230V AC) switching using a Triac BTA12-600B. I fed the signal from a microcontroller to an opto-triac coupler MOC3041. The LED bulb turns ON and OFF without any issues.
Please note: I am using the LED only for ON/OFF purpose (no dimming).

Below is the working circuit.

without snubber

Now I add a snubber circuit in between just to protect my Triac in case of overvoltage. Below is the modified circuit

with snubber

Now comes one big issue:

The LED bulb flickers repeatedly, think at the rate of 50Hz or more. I am unaware of the internal circuitry the LED bulb has as it is enclosed in a retrofit case.

I feel, addition of snubber circuitry is causing the flicker because the LED bulb never flicker when I used the circuit without snubber.

Any reason why the LED flickers and its possible solution ?

Thanks in advance

Best Answer

Your config seems a bit odd to me. You may try this one:


simulate this circuit – Schematic created using CircuitLab

Note that the snubber cap C1 may be 10n to 100nF.