Improving an existing LED Driver

[DSpeegle]

Hello ! I have a WiFi LED driver that we purchased that has visible flicker when its dimmed below even 80% using its own dimming software. What would you suggest for me to upgrade in order to remove the flicker? What would cause the flicker? In general, how can I improve on an existing driver to help reduce flicker?

 

[DSpeegle]

Buck converter.. Ok, thanks for the information. I'll certainly look into that. Do you think that running it through a microcontroller would eliminate that step? Since it would be outputting square waves anyhow?

 

[zappedagain]

"Have you tried contacting the seller to ask if they would sell you a version with a higher PWM frequency? "

Are you sure they haven't already fixed this problem because others have complained about it? If the issue is on the web or social media there is a good chance that they paid attention and fixed it fast with firmware, so a new unit may not have the same problem.

Z

 

[DSpeegle]

Thing is that they have it output at 600 hz which is high enough for most normal applications. It's just not good enough to use on video. I will contact them and see if they would be willing to modify the coding for me. Next, I'm going to run the signal through a microcontroller and output it at a faster rate, does anyone know of a reason that wouldnt work?

 

[IRstuff]

That's a lot of work just to get rid of "flicker."

The issue that you're having with the camera is that the actual time that the detector is actively integrating photons is extremely short, typically less than a few milliseconds. At 10 kHz, you'd get a minimum of 10 PWM cycles within the integration time of the camera, which is what minimizes the observed "flicker."

The simpler solution is to stick a neutral density filter to drop the amount of light coming into the camera to force the camera's AGC to increase the integration time. A 1.0 ND would decrease the light by a factor of 10 and force the integration time to correspondingly increase. If the camera lens has a physical iris, then stopping down the lens would be equivalent.

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