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WS2811 SPI to RGB Decoder

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EvilGenius

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Hello
I have been searching for months on internet to find something similar to what I am looking for, to no avail.
I am trying to find a decoder (WS2811 Based) that coverts SPI signals from a controller into RGB+ and have the ability to use 12VDC source to drive RGB modules of 1A per channel. There are lots of products out there (including 5V intelligent strips) that use similar protocol and drive simple RGB LEDs (utilizing WS2812 & WS2812B). However these designs are limited to individual RGB LED at low currents.

Concept: Data In, Data Out, RGB Out. Daisy chained Di-Do for number of decoders. Each decoder controls one RGB module at 12VDC @ 1A per color.
Data in is received from a controller (lots of choices out there), grabs 24 bits for colors, displays them on RGB, and pass on the rest of data chain to the next decoder. It is almost like an intelligent strip with the difference that it drives 1A per channel for R,G,B instead of normal 18mA per channel.

Any suggestions of products or sites are very much appreciated.
If I am not able to find such product, I will attempt to design one. I am open to any suggestions.
Regards,
Rom
 

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  • WS2811 SPI TO RGB DECODER 12V.pdf
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They must be available.... RGB strip lighting uses some serial device.. The one's I've seen seem to have several LPD8806 chips they have serial in and PWM out to run two RGB's
Datasheet:-
45182-led1.jpg
 
They must be available.... RGB strip lighting uses some serial device.. The one's I've seen seem to have several LPD8806 chips they have serial in and PWM out to run two RGB's
Hi Ian
I run into the same thing out there. These are all designed to drive RGB at low current (individual RGB) and not high power (1A-3A). I even went as far as contacting several manufacturers in China and distributors of RGB controllers online and they all said the same thing. They do not have a product of such available. This decoder will be extremely useful and in demand. It will be an easy and fairly cheap interface that can drive higher current RGB modules. They will come in handy for architectural lighting, wall washing, landscape lighting, xmas lighting and so on. In a sense they will be like the strip you posted but in much higher power. each decoder connects to an RGB module and daisy chained. Each RGB module could be several feet away from each other! (since WS chip has signal conditioning)
These decoders essentially will work exactly like what you described and will accept multiple signal protocols. From signal perspective it is a chain of WS2811 (or similar) following each other. But each decoder can sink much higher currrents from mechanical perspective of it. Look at the PDF file I posted and may be you can see what I am trying to do!

Thanks for your reply,
Cheers.
 
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Take a look at the WS2801 IC. It is very similar to what you need. On page 10 is shows how to use a NPN transistor to power higher power LEDs
Thanks OverClocked for your response. WS2801 is a synchronous SPI device. While WS2811 is asynchronous device.
The difference between the two is that WS2801 requires a contant clocking to synchronize the modules while WS2811 does this with "stop" command as part of the received data and does not require an additional clock. For that reason WS2811 only needs one communication line while WS2801 needs two. Attached is a datasheet for WS2811. The concept of driving higher currents via transistors in WS2811 is a bit different. In WS2811 you will need a PNP-NPN Totem-Pole configuration since WS2811 sinks the currents instead of driving them.
I was looking for an inexpensive pre-made tiny module with drive/sink transistors built-in. I have designed such module and have been able to reduce it to a 0.5x1 inches in dimensions (smaller than a tiny RGB amplifier). I was just checking if such product already exists at a low cost. If not, I have to build my own SMD circuits.
 

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  • WS2811 Datasheet.pdf
    315.7 KB · Views: 294
Quick Update: I looked at different ways of manufacturing the part I need in U.S. as well as in China. Like any other product you have to produce and order large quantities along with engineering specs, bill of material, provide them with SMD parts, pay for board, assembly and shipping. Even with large quantities in production, I can not beat the cost of combination of already made products. In conclusion unless some manufacturer comes up with the ready made product all in one very cheap, I opted to use two small devices instead. 1- 12V WS2811 SMD PCB (Boards used for RGB nodes) which includes Data in, Data out, RGB out. Max sinking capability of 20mA per channel. 2- 12V RGB SMD Amplifier. This product amplifies RGB (20mA) upto 4A per channel and feeds off 12V supply. Here is how it works: SPI signal arrives from TinyPixel or SPI SD-RAM card controller in the form of +V, Data, Ground. Also +12v and Ground from Supply feed into the WS-PCB. At the same time WS-PCB provides SPI data to the next RGB+ module. The RGB+ output of the WS-PCB simply connects to RGB input of Amplifier and output of Amplifier connects to 12V RGB Module up to 4A per channel (R,G,B). Amplifier also has a separate +12v and ground supply line that can be connected to WS-PCB and 12V supply line pair. I was able to find WS-PCB online from China at about $0.30 each and RGB Amplifier for about $1.10 each. Total cost of parts including free shipping $1.41. The rest is just simple wiring. WS-PCB board is 10mm x 20mm, and RGB Amp is 10mm x 25mm. Both can be wired to be inline for each RGB module.
 
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"Even with large quantities in production, I can not beat the cost of combination of already made products."

Many of us have also arrived at the same conclusion.
 
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