Multiple power supplies, Different Voltages causing flicker

I’m trying to setup two led strips one is 24v and the other is a 5v ws2812b. I’ve tested them individually and everything works correctly with an esp32.
When I connect both, the white works fine but the ws2812b starts to flicker.
I’m using a logic shifter and have tied the power supply grounds together.

Can anyone help?

What’s the distance from the ESP32 to each strip?
What’s the length of each strip?
What’s the capacity of the 5V power supply?
You say “the white works fine” so does that mean the 24V is a white Analog strip?
What GPIO pins are you using for each strip?

Thanks for the reply, for testing the distance is around 30cm with each strip being 1m.
The 5v supply is rated for 6A. Thats rights its a white cct strip that’s being controlled by mosfets.
The ws2812b is connected to gpio 16 and the cct is connected to 22&23. Although i’ve tested on other gpio with the same result

I’d focus on making sure the MCU power supply is solid if you even have to attach a separate small 5V1A directly to the ESP32.
After that try reducing the WS2812b brightness down to 30% to see if you may be having dropout issues.
Lastly, you might try to reflash with a more recent version of WLED.

I’ve tested powering the MCU seperately and im running the latest release of wled. It seems as through the issue is related to grounding. Probably due to the difference in voltages but im not sure how to fix this

Which shifter are you using?

A 3.3v to 5v bi directional shifter from amazon

Which? It may not be one that works.

Those transistor ones are intended for I2C and are too slow.

See here under Levelshifters.

Thanks for the help, I’ll swap the shifter out and see if that helps

There are any number of cases out there with both Addressable and PWM strips simultaneously working just fine.

The Mosfet for PWM is what you need, the “cheap amazon level shifter” may or may not be an issue. Just because you can hook up a scope and see what looks like a clean waveform doesn’t mean it doesn’t perform poorly when asked to do a fast transition at some part of the data stream. You’d have to be able to isolate the data at the exactly the point of the flicker.
If you can keep the distance between the ESP32 and the 1st WS281x LED very short you can try without the levelshifter at all.

That all said, what version of WLED are you running and how did you flash the software?
What GPIO’s have you tried?
What’s your info for FS and heap memory look like?
What happens if you decrease the number of LED’s down to a very small (15) number?
What size power supply(s) are you using?

I’d suggest using ESP32 for testing, it will be more flexible about memory and GPIO usage.

Are all your 24V, 5V and ESP32 grounds/0V linked? You must have a common ground/0V with any multiple PSU configuration.

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