How to light SK6812 strip with Warm White / White / Amber LED's?

Is anyone familiar with this LED Strip? A SK6812 variant with Warm White / White / Amber LEDs.

Wondering if Pixelblaze can handle it and how? I know everyone here is focused on COLOR, but I am experimenting with sculptural ‘table lamps’ that have a pleasant white light so as to be functional and some ‘easy on the eyes’ moving color as decoration or sparkle. I’ve been thinking along the lines of RGBW strips. But this white color combo might create unique ambiance for some pieces.

Warm White / White / Amber

LED source :5050SMD WWA built-in SK6812 chipset
IC Type:SK6812
Working Input Voltage: 5VDC
Output power: 0.3w/ leds
Drive Mode:Contant Voltage
LED Quantity: 30 60 74 96 144 leds/Meter (each LED is separately controlled)
IC Quantity:30 60 74 96 144 IC/Meter (1 IC drives 1 led chip)
Pixels : , 30 60 74 96 144 Pixels/Meter
Grey scale:256
Color:WWA (Warm white:2700-3000K, Cool white:6000-6500K, Amber:1800-2000K)
View angle:120°
Working Tempreture:-20° to 60°
PCB color: Black/White PCB
Waterproof: IP30 IP65 IP67

Cuttable: every LED is cuttable

LED light source: SK6812-60L-WWA

Use RGB, where RGB is really Ww/Cw/Am (in some order)

So it’s pretty simple, if that’s how they wired it as addressable.

To be clear: this strip has no color leds, just those three leds instead.

Yes, that’s right, just those three whites.

I understand the the Pixelblaxe is compatible with at least RGBW strips. How about RGBWwCw strips?

How do you code for white(s) on PB using a SK6812, 4 or 5 color chip?, do they have formal abbreviations like Ww, Cw?

I understand that the WwCwAm strip, in my original question, is still a 3 color chip so it’s a direct swap for RGB. But, now I’m curious about these 3+ color LED.

Just so I’m clear on what the PixelBlaze ends up sending to the chipset…it’s code containing the 0-255 intensity for each color in the chipset, in the order that the chip manufacturer assigns them? That’s why we have LED strips with different color order, and why PB allows you to change up the order that it sends the brightness info in. And that data is filling an 8 bit output register assigned to each Color LED, and after the first 8 bits, then it overflows to the second color register and so one. So a 4 color chipset is expecting to grab the first four 8-bit chunks of brightness values before it forwards the data stream to the next chipset? So in order to light up a 5 color LED chipset, PB needs to send five 8-bit intensity values for each color on the chipset followed by some period of time before latching and then sending the colors to the next chipset. Have I got this right?

So theoretically PB just needs to know how many colors are on the chipset and their corresponding brightness values, to turn on any or all of the them . This sounds so simple and clear now that I’ve laid it out. Not that programming the PB to do that is simple! And I assume it is not programmed for more that 4 possible colors, and even 4 might require the use of the output expander?

Thanks for letting me talk to myself here…it helps My old brain.

There are 2 modes based on the color order selection, RGBW / GRBW which use the white element automatically, and RGB-W and GRB-W that don’t use the white element at all.

For RGBW support, white is automatic, and is borrowed from R+G+B values.

For example, if you had a color that ended up as (red=255, green=127, blue=32), then 32 is removed from each and sent to the white element, resulting in (red=223, green=95, blue=0, white=32).

WWA LEDs aren’t officially supported in that there aren’t any specific features for them. I’ve seen these in both WS2812 compatible protocol, and APA102 compatible protocol. You can still send these data using the rgb() API and doing your own calculations to mix the elements for desired effect.

Only 3 element RGB and 4 element RGBW types are supported. I haven’t seen any 5+ element addressable LEDs, not commonly available using one of the supported protocols anyway.

The output expander likewise is designed for 3 or 4 element RGB / RGBW WS2812 compatibles, and RGB APA102 compatibles.


Thanks for taking the time to explain that; it’s very clear… sounds like a good strategy.

So, if I wanted only 60% white, I’d send a brightness value of 153 (60% of 255) to each color R,G, & B and PixelBlaze will sub in the white.

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Yep, and in code it would look the same for either RGB or RGBW LEDs:

rgb(0.6, 0.6, 0.6)