LED stripe flashes randomly

Hello all together,

as shown in the picture, I finished my hardware setup. But now I have the problem that the LEDs flash randomly, when I like to set a color or effect. A few more information to the circuit:

  • Meanwell 100W, 5V power supply
  • ESP32
  • 4 LED panels (each 89 LEDS; data wire serial and; power supply parallel for each ~30 LEDs)
  • 2m Wire of 0,75mm^2 between circuit and LED panel
  • controlled by the WLED application at the pc via wlan

Do anyone have an idea how to solve this problem or how I can proceed to find a solution?

I found the following statement, but don’t know how i should understand this:
“The data output from the Pi is in the form of a voltage - either 3v3 or 0v - between the GPIO and the Pi’s ground. The data the lights expect to receive is the difference in voltage between its data input and its ground. Unless the two grounds are connected together - the same reference - the lights can’t make sense of what it receives.
So join them together.”

Could my GND be the problem?

You most likely need a level shifter. Getting Started - WLED Project

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Thanks for the hint! In the datasheet of the LED stripes (WS2812b) I found the information, that the Voltage for the data should be 0.7*V_DD at least - but no maximum given. As I have seen, in most projects like this, the people use 3,3V to 5V level shifters. You think 5V are also adequate for me?

Update: I removed the resistors from the data line and it works fine now.

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