What modifications can be made to a TRIAC-based dimmer circuit to reduce flickering in LED bulbs at low brightness levels? The current setup uses a potentiometer for control in a DIY home automation system, but experiences noticeable flickering when dimming LED lights. Can anyone help to address this common issue?

 

It's not so simple, I think. Specific LED drivers are used to correct it.

This may help:
https://ozuno.com/blog/phase-dimming-a-tutorial/

 

It's not so simple, I think. Specific LED drivers are used to correct it.

This may help:
https://ozuno.com/blog/phase-dimming-a-tutorial/

Then you have to apply that to LEDs. What happens is that the output from the phase-fired dimmer is rectified and smoothed to make a supply for the LED driver. The circuitry also obtains a pulse-width signal from the incoming dimmed waveform. That pulse-width signal is then used to control the current to the LED which runs off the rectified and smoothed supply.
At some point, at low dimming levels, there won't be enough voltage to make the supply for the control circuitry to work. At that point, it runs for a while - the supply drops and it turns off, the supply builds up again. It restarts and the cycle repeats.

The most important point here is that There is NO standard for what constitutes "dimmable".
The whole system is a complete dogs' breakfast.
If you want to dim LEDs do the job properly from the beginning, and installed controlled dimmable ballasts. Otherwise it will be hit-and-miss. When you change to a different brand of so-called "dimmable" LED lamps, they may work or they may not. And they can be called "dimmable" provided the manufacture at one point made them work to a satisfactory standard (who determines "satisfactory"?) on a dimmer somewhere, once.

 

Replace your lamps with those labeled "dimmable".

 

Replace your lamps with those labeled "dimmable".

. . . and hope for the best.

 

Hello,

I have used an expensive philips dimmable led lamp.
It had a much worse responce on the dimmer than a cheap LSC dimmable led lamp from action.
You must have some luck with the dimmer and led lamp combination.

Bertus

 

The first step is to verify that the LED lights are claimed to be "Dimmable." If not, it all depends on luck.

 

It's not so simple, I think. Specific LED drivers are used to correct it.

This may help:
https://ozuno.com/blog/phase-dimming-a-tutorial/

Thanks a ton for sharing this!