Hi folks, after many months of other activities,

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Hi folks, after many months of other activities, i finalized my LED setup in the basement for the disco lighting for my kids. I have put a total of 1144 LEDs into the edges of the ceiling for an indirect effect.

I am using OctoWS2811 with 8 parallel outputs to segments of 150 LEDs (last one obviously shorter). At one point I need to break the WS2812 strip for around half a meter and transfer the data signal from the output of the strip end to the input of the next strips start. For this I am using one of the leftover cable pairs of the CAT5 cable I used with the OctoWS2811. The pair has the signal and ground and is still drilled.

However, I seem to have a bad signal quality at those LEDs that are coming after this distance, before the next segment starts. When I turn the power supply and the Teensy on, it works normally but after a while those few LEDs (around 70) flicker and stay in some random static color.

I have already increased the voltage a little bit to 5.2 V. I am not sure what is the highest voltage I should use at max.

The ground line of the drilled pair is connected to the power supply ground cable very close to the LED which is outputting the signal.

Do you have any recommendations how I could improve this? Should I place any capacitors or resistors?

I am asking because its not so easy to try things out now that everything is installed, the strips are difficult to reach, etc.

Thanks!

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Don’t up the voltage - I’ve seen ws2812’s have signal problems as the voltage goes up. Also, are you injecting power to the strip?

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@Sebastian_Stuecker Every LED has a signal former that provides a clean signal for the next LED. There are two approaches you could try, but first double check that you have a good ground connection (!)

a) If the signal degenerates for some reason over the distance you can use a single WS2812 half way in between.
However, I would expect signal degeneration at length of >2m.

b) It looks more like a signal reflection. Use a Source Termination Resistor at the OUTPUT of the first LED strip.
Take a 100 Ohm pot and see whether one setting eliminates the problem. Measure then the resistance and replace the pot.

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Hi @Daniel_Garcia , there is power injection around every 2 meters along the full setup. i ran tests with full brightness in white for several minutes without any temperature problems and also no visible effects of voltage drops. Its powered with a 5V 80 Ampere supply.

I will see if I have a pot and try out Juergens advice.