I could use some help debugging a problem with a project that uses a

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I could use some help debugging a problem with a project that uses a fairly large number of WS2812 LEDs – around 700. The behavior is that the display generally works as it is supposed to, but occasionally a section of LEDs flashes white and then goes back to its proper color. Sometimes, it actually gets stuck, as if the signal is not getting through. The colors are correct up to the affect part of the strip, then they are stuck from that point until the end of the strip.Unplugging and/or restarting the system does not always fix it.

I have the LEDs powered in groups of 30-40. The voltage at the end of the strip is around 4.7V-4.8V. I am level-shifting the signal, using a widely available logic-level shifter (but not the one widely recommend here).

Calling on the FastLED hive mind: does this sound like a signal problem? A programming problem? A power problem? I’m not even sure how to go about tracking down the problem.

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Which level shifter? Seems a likely culprit.

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If it’s always the same place, I’d guess an intermittently faulty led

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Yes, faulty led or bad solder connection to the LED.

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I had same behaviour on some strips it is generally a led which is about to fail. You will need to replace the faulty one ( what I do is replacing the last one that works and the first one that stays white this way I am sure )

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I have had that problem on strips and found the data line to have a bad connection as well. I think adafruit recommended a small resistor between the pin and the start of the line. For me I redid the data line and it worked fine.

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Thanks all! I will try replacing the logic level shifter with a better one, and take a look at the data connections. I’ll let you know what happens.

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@Sam_Guyer good luck

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I’m seeing this quite a lot, even with WS2813 LEDs with have data redundancy. When I replace the faulty LED (plus the good one before it, as Tim does), then often that section of the strip continues to have problems, like several LEDs not consistently turning off.

One thing I’m wondering is if it’s an ESD problem, as I definitely don’t follow proper ESD protocol when working with the strips or my controller. Especially when soldering in replacement LEDs “in-place” (on a house roofline).

@Sam_Guyer please keep us posted on what you find!