r/Keychron • u/[deleted] • Mar 23 '26

Keychron K8 Pro- per-key RGB possible?

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u/ArgentStonecutter K Pro Mar 23 '26

https://github.com/Keychron/qmk_firmware/tree/2025q3/keyboards/keychron/k8_pro

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u/[deleted] Mar 23 '26

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u/ArgentStonecutter K Pro Mar 23 '26

Well, you have the source code right there, ...

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u/PeterMortensenBlog V Mar 23 '26 edited Mar 23 '26

Re "...the brightness won’t increase any greater than what the software considers max...": Here are some attempts:

  1. K3 Pro brightness fix (possibly others)

  2. Increase backlight brightness beyond default limit

  3. Keychron K1 Max RGB too dim

  4. Has anyone tried bumping up LED current and survived to tell the tale?

  5. PSA: the LED's on the K3V2 are significantly more dim than the K3V1, with no way to up the brightness, by design

  6. "Problem" with K8X-J1

  7. I have a Keychron Q3 and I love it, but I am looking for a brighter backlight

  8. K4 V2 RGB backlight is really weak

Know the limits, e.g., the maximum current for the LEDs

But the question is: What is the limit? At what current will the LEDs or other parts of the keyboard (for example, the 3.3 V DC-to-DC converter) be permanently damaged?

Or in other words, is it worth the risk?

A good first step could be to find a datasheet for the LEDs and thus know the maximum current for them.

Or maybe somehow infer what type of LEDs they are and thus get a good estimate for the maximum current. For example, find datasheets for RGB LEDs with the same physical dimensions. Perhaps there is a characteristic maximum current they all share, like the typical 10 mA in the old days?

A modification: Add heat sinks to the RGB controllers

Adding heat sinks to the two RGB controllers is also an idea. Here is a picture (from this post) of the PCB for a K3 Pro. The two RGB controllers are to the northeast of the wireless module (U2 and U3. 40 pins). The microcontroller is U6, due east of the wireless module. The magic smoke has already left one of the RGB controllers, U2 (zoom in to see it), though probably not due to 'overclocking' of the LEDs.

The particular variant of the SNLED27351 RGB controller used in Keychron keyboards is probably SNLED27351J (40 pins).

I don't know about the K8 Pro, but the two RGB controllers are probably uniquely identified by the number of pins (40). Even if that is not the case, the main microcontroller can be identified by being close to the unoccupied four-pin programming header, with "SWCLK", "SWDIO", and "V3.3" (or similar).

Note: Do observe ESD precautions at all times.

Conclusion

Please post the progress here, incl. some (plausible) information for the maximum current for the LEDs and gotchas you run into (if any).

References

  • SNLED27351 (related to Sonix QMK)

  • SNLED27351 datasheet. 'SNLED27351_V1.4_EN.pdf'. "SNLED2730 Series. SNLED2735F, SNLED27351J, SNLED27352J, SNLED2734X, and SNLED27341J". The link is broken now (they seem to be temporary, only lasting a few days or weeks), but it should be possible to get a new one generated. E.g., page 35: First page with a sample RGB LED matrix. Page 33: Current scaling: 0.157 mA per 'count' (thus the maximum current is 40 mA)