SK6812 24V - No control. Help needed

Hi, I’ve bought this Strip. Now I try to get it working with a QuinLed DigUno wich work fine with a WS2812B 5V Strip.

The SK6812 strip does strange things, sometimes the Leds lights up in different colors, sometime just a few lights up. I have no control, no solid color, nothing. I’m on the latest Version.

Maybe the Strip is not supported? Hope someone can help.

Thanks

Hi and welcome to the forum , While I do not have SK6812 or QuinLed , The strange thing is my reference as well as wled page mentioned SK6812 as 5V . But the link you give mentioned 12 V and 24V .

What is the voltage written on the SK6812 you got ? Might be this is the issue ? Just make sure you are careful when switching power supply as my understanding on the DigUno you have to manually set the jumper to match your strip voltage ( meaning if you power it by 12V and the jumper on 5V then you could damage the board which I have seen happens to a friend )

https://kno.wled.ge/#compatible-led-strips

Did you choose SK6812 RBGW as the output type in LED Preferences?

Hi, thanks for your answer. The voltage of the Strip and the Power supply are 24v. This 24V i can measure between V+ and GND. The LEDs lights Up but i cant control anything. No Matter what i try. At every reboot the Leds have different colors and brightness.

Yes i choose SK6812 RGBW as Output Type and also try all possible Color Order.

I thought the voltage doesnt Matter because the Chip SK6812 ist supported by Wled.

The Stip is a RGBWW .Maybe thats a Problem?

Here a Pic how my Strip Look like

The strip voltage shouldn’t matter as the data line should still be 5V. Have you tried any other protocols just to see if you can get any control?

Does your Uno still drive a WS2812 properly?

If you mean with “other protocols” different LED Types, then yes. I tried every digital type without Clk. Same Problem, no control

If I change the power supply and the jumper to 5V a WS2812 Stripe works fine. Everything possible, solid color, effects etc.

after a couple of hours trying I can control the solid color but only after turn the power supply off and on again.

Settings:
Output Type: SK6812 RGBW
Color Order: RGB

if I hit the button for example solid color green in the webinterface, nothing happens. If I now turn the supply off and on, the whole strip is green. this works with any color but unfortunately not in real time…
but some “control” seems to be possible

next problem , no matter how many leds are configured, the whole strip lights up. but after power off and on the voltage only the configured leds change the color execpt the first led…it does what it want.

In my case 1 led means 6 Leds because one IC drive 6 Leds.

Maybe someone has an idea

Thanks

Hi
Maybe it works when powered on, because Vdd is low compared to Vdata for a few ms.
Maybe it needs a level shifter to 24V Data ? But just guessing.
I guess the supplier is of no help ?

SK6812 RGBW/WW DC24V Must Use DC24V Power Supply AND Led Controller to Control!

Whatever that really means.

All LED data lines need 5V.

Data is 5V TTL. 12V and/or 24V strips simply stack the LED’s and/or add series resistors to handle higher voltages safely. The data line is still 5V. Have you actually measured 24V along the strip? Can you measure for 5V on the Quin when powered at 24V?

The other thing to try is power the strip directly from 24V, power the MCU separately from 5V and connect to the strip with ONLY a ground and data wire. The ground from the 5V and 24V supplies will be connected together at the strip (that’s safe) and the data wire goes from the MCU to the strip.
DO NOT tie the +5V and +24V together - that won’t end well.

That way the MCU is running on 5V (which works) and the strip is at 24V which is what it needs.
Eliminates possible issues with your 24V supply or the Quin not converting down properly.

Thanks for the clear response.

This data sheet tries to tell me something different. But it is also internally mixed up.

First, thank you for your support! I have control now. I only connect the data wire to the quin and the power supply directly to the strip and parallel to the quin power input. Solid colors, effects, everything works now except the white channel.
If I change the color to something with white added in, the strip starts to flickering and randomly change the colors.No matter how the brightness is set. I activate the White Balance correction and try all calculate options. Accurate seems to be the most stable option buts its not very bright. If I configure dual for example, the strip is much brighter but freeze for seconds if I try to change the color again.
Also the power consumption is strange. When I configure solid white with brightness set to maximum (sometime it works and stay white) the strip consumes a maximum of 35 - 40 watts. According to the specs the strip should have 18W/m

What version of WLED are you running?

  1. Get up to V0.13.0-b6
  2. Turn off ALL the White calculation colour features, stick with setting them yourself for starters.
  3. Disable the brightness limiter or tell it you have a PSU capable of 65000mA.
  4. Try setting 1 of the RGBW channels at a time with no other channels on. Verify that you can control each by themselves.
  5. Start adding in multiple channels and mix with W.

You might do all these tests with a small number of LED’s (say 20) for starters, then expand once you think it’s working as it should.

I´m on V0.13.0-b6. Ok, disabled White calculation. Limiter was disabled. I can control each channel by itself. Everything works fine. i figured out that the white channel is not the problem. The flickering begins when I mix RGB, but only when i mix all three of them. The configured number of LEDs doesn’t matter. currently I have 3 configured.(3x6 LEDs)

That sounds very odd.
It almost sounds like an issue I had with a completely different kind of SK6812RGBW strip.

Try something, use the full strip at 100% brightness.
Adjust only 2 out of the 3 RGB Channels, leaving W at 0 and the 3rd channel at 0.
You should be able to adjust any 2 to give different colours with no flicker.
Then try to add the 3rd channel in does flicker start?
Go back to 2 only at 40% and 75%, no flicker?
Try adding in White, somewhere around 30% does flicker start?

It sounds like you might. But I want to verify that you have all the grounds tied together.

Tried that.

You should be able to adjust any 2 to give different colours with no flicker.

correct. For Example Red and Green… no flicker

Then try to add the 3rd channel in does flicker start?

Yes, when I add blue(just 10-20%) it flicker immediately

Go back to 2 only at 40% and 75%, no flicker?

correct, just Red and Green no flicker

Try adding in White, somewhere around 30% does flicker start?

yes flicker start, but not as much as before when I add blue to red and green

This is starting to sound really ugly.

My experience with this was a different type of RGBW, 5V pre-soldered with 1cm boards on 10cm wires.
Worked great (I thought) except for a few flicker issues with particular colour settings. Blamed it on my Arduino code forced to run on an ATTiny85 MCU (very small, 512K RAM). Didn’t need effects so ignored the flicker.

Jump ahead 2Yrs, someone else complains of similar issues with a SK6812 RBGW string that looks suspiciously like mine. They further diagnose something I never thought of: the onboard 75R0 resistor.
Normally that resistor is inline with the Do pin, giving some noise tolerance. On these boards it was inline with the chip Vcc pin!

That means power through the chip was limited by a 75 ohm resistor, messing up the supply voltage as brightness increased. It caused all the weird effects noted above. The final solution on my strings was to bypass/remove the resistor completely. You can see some more details here: SK6812 RGBW unstable - #19 by divsys

Your strings are a little more complex as there is only 1 “smart” LED in each block of 6. I’m willing to bet if you spent some time with a multimeter, you’d find a resistor inline between the 24V power line and the VCC to the smart LED.

Unfortunately, I don’t have a solution for you as I don’t have any specs on the smart LED in your strips. I don’t know if it can live connected directly to 24V or not. I suppose you could try and sacrifice I block of 6 and try it out. Just be prepared for smoke…

Interesting, just to chime in, I’ve used 24v sk6812 (and ws2811, TM1814) without an issue before. I actually made a little video about it. :slight_smile:

So not sure what is causing the issues but if you’re running one of the more recent versions of a QuinLED pre-assembled board, 24v is fully supported and “should just work”. :slight_smile:

I tested everything at varying brightness, including full, white channel enabled, everything as shown in my 24v real-world measurement sheet.

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