Anyone ever have the issue of flickering leds where touching the MCU causes the

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1

Anyone ever have the issue of flickering leds where touching the MCU causes the flickering to go away?

I realize this is a grounding issue, but not entirely sure why it’s happening inconsistently and what the right way to fix this is.

Thoughts? (using the nodeMCU)

2

Try adding a capacitor across the power and ground. Close to the LEDs. Basically your hand provides some capacitance to the circuit removing the flickering.

3

this is helpful thank you!

4

@Dushyant_Ahuja ​ any particular reason this would happen with battery powered projects but not ac->DC power supplied situations?

5

@Lucas_Morgan not sure, probably your dc-dc converter is not smooth enough.

6

Interesting actually the capacitor did not help in this situation.

7

Are you using a level shifter?

8

I also had this issue with ws2812b strips and the Nodemcu. I thought it was a loose connection at first since holding it fixed the problem. But Adding a 74HCT245 level shifter fixed it right up

9

Maybe this will help: https://todbot.com/blog/2017/01/12/crashspace-bigbutton-w-esp8266/

10

I had a similar issue from an old project. It turned out being a ground loop when I started running the audio amplifier circuit. I never fully fixed it even though much time was spent tinkering with an oscilloscope. Making all of the wires as short as possible and adding a large capacitor like mentioned above fixed the problem most of the way. look into ground loops. They are no fun.

11

also when I touched the circuit the problem went away.