I have a large number of addressable, 3-Wire RGB LED's. (Power, Data, GND)

I don't have any information about them, so I autopsied one to see what's inside.
The chip seems to be a GW6202B, which I find only sparse reference to on the Internet, just a few pages about LED's and addressable controllers, but NO DATA SHEETS? It seems super odd that I cannot find the data sheet for this beast?

I did find a partial description on a Chinese page, but it has nothing about the pin-out or protocol.
It looks to be a 5V unit, as it says "+5V" on the PCB.

I am hoping it uses a protocol similar to the WS2812 chip, which uses a pulse-width coding scheme- I wrote a PIC32 DMA based driver that works great for these parts.

Anyone have any experience or knowledge about the GW6202B part?

 

Hello,

I also can not find any info on the chip.
It is likely an OEM product.
It looks like 4 wire to me.
The DO is likely the SDO signal.
The DI is likely the SDI signal.

Bertus

 

hi,
This is all I could find, perhaps a contact email query may get a result.
https://detail.en.china.cn/provide/p118621983.html

E

 

Hello,

I also can not find any info on the chip.
It is likely an OEM product.
It looks like 4 wire to me.
The DO is likely the SDO signal.
The DI is likely the SDI signal.

Bertus

Correct, 4 wires - DATA IN, DATA OUT, GND and +5V

I'll shoot the vendor above an E-mail, that's a good idea.

 

Update-

All signs pointed to the GW6202B chip being compatible with the WS2812 protocol, so I thought I would just try it and see if it works- and it does!

I am using my PIC32 Direct-Memory-Access (DMA) solution, which uses the DMA engine to output SPI data from a bank of RAM to generate the PWM coded pulses required by the LED chips.

I use a simple lookup table to map the LED brightness into a pattern of bits, each data byte value points to a 32 bit constant that represents the pattern for the PWM waveform, 8 data bits expands to 32 bits of SPI data.

This scheme allows sending the LED data without CPU overhead and produces a jitter-free output waveform.