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This kit is an Arduino shield to control a Red/Green/Blue LED board. Use it to help add colour to your projects.
It contains an IC which controls the output colour PWM using serial commands. If you need to change the colour then just send a new colour setting.

These units are also stack-able so you can run lots of large RGB units from just two digital pins.

This boards was dsigned in conjunction with Phenoptix, who supply LEDs and kits for makers 

It is available here via Tindie or direct via paypal. This kit is OUT OF STOCK and there are no plans to re-introduce it at present.

Please Note: This page is for information only as this kit is OUT OF STOCK:

This Arduino shield controls 3 outputs for red, green and blue with pulse width modulation. These outputs can control any 12V load, up to 1.5A.

This has been design in conjunction with phenoptix to interface with their 12V RGB LED boards (designed by Big Clive).

The circuit uses a serial interface and pulse width modulation (PWM) control to maintain an output colour. It is based upon the WS2801 RGB LED controller IC, but has higher current output buffer transistors which means it can be used with higher current and higher voltage RGB LED displays. Only two Arduino digital IO pins are required to control virtually any number of RGB led boards.

The board has an in-built 5V regulator to power the Arduino from the input supply.

Please note: This kit requires both an Arduino (or another micro-controller) and an RGB LED unit.

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This is the shield plugged into an Arduino base and wired up to a 12V RGB LED unit.

Here is the example code (available below) in action:

Buy one here:

This kit is available to buy via Tindie.

Or direct via paypal:

This kit is OUT OF STOCK and there are no plans to re-introduce it, as there are many other RGB LED controller available.

Kit Information

This is a relatively simple to put together kit, but there is one surface mount device to solder. The kit includes these parts:

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Note: You will need: soldering iron, solder, wire cutters, small pliers.

Instructions

The construction instructions are available here:

Design Overview

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The input voltage (at P1) can be in the range of 7 to 30V DC. It is designed to be used with 12V LED boards, hence the supply will need to be 12V DC.

An on-board voltage regulator gives 5V to the shield and also powers the Arduino board.

This shield uses the WS2801 RGB controller IC. This reads in serial data and then controls three pulse width modulated channels (one for each colour: red, green and blue). The data sheet for the WS2801 is available here: http://www.sparkfun.com/datasheets/Components/LED/WS2801.pdf.

Once the output colour has been set using the serial interface, then the Arduino does not need to do anything else until the RGB LED needs to be changed, as the PWM control is handled by the WS2801 IC.

The output from this IC can only control a maximum of 20mA, so additional transistors have been used to control a higher output power than this (up to 1.5A).

This board is quite hackable, for example:

Stacking Multiple Boards:

These boards can be stacked to have multiple RGB outputs, although some changes and extra components are required. Here is a guide to the changes required if you would like to stack these boards to run more than one RGB LED shield from an Arduino.

Please check the circuit diagram and instructions for more info or email us at: This email address is being protected from spambots. You need JavaScript enabled to view it. .

Circuit Schematics

Here is the circuit schematic:

Edit 21/10/14: The PNP transistor shown in this diagram is the wrong way around (emitter and source should be swapped). This is incorrect on the schematic, but correct on the PCB. Thanks, Vadim, for pointing this out.

Parts List

The kit includes the following parts. (As noted: you will also need an Arduino micro-controller board and some form of RGB LED board).
 
Ref
Description
Value
C1
Capacitor, electrolytic
100uf 25V
C2
Capacitor, electrolytic
10uf 16V
D1, D2
DIODE
1N4001
K1
PWR_OPT
Just a wire connector
P1
2 way socket
12V Power
P2
2 x 2 way socket
For RGB LED
P3
POWER
Not supplied – for multiple boards
P4
DATA
Not supplied – for multiple boards
 
PCB pins
To fit into Arduino – Long Pin
Q2,Q3,Q5
Transistor
BC556 PNP
Q1,Q4,Q6
Transistor
BD135 NPN 1.5A
R1,R3,R5,R7,R9, R11
Base current limit resistor
1k
R2,R4,R6,R8,R10,R12
Base pull-down resistor
100k
 
PCB
Arduino Shield – Double Sided
U1
Voltage regulator
78L05
U2
RGB LED controller
WS2801

Arduino Code

The code for this project was written using the Arduino bootloader and IDE. (Note: It was written in the latest version 1.02 of the IDE and is untested on other versions).

This project assumes some knowledge of the Arduino platform. If you do not have this then please start with the numerous examples available within the Arduino community.

Here is the example, which you will need to download and add to your Arduino sketchbook:

The code has numerous comments and is based upon sample code written by Nathan Seidle via Sparkfun Electronics.

Here is the example code in action:

KiCAD design files

This is a fully open-source project. The PCB and schematic for this project were drawn using the open-source KiCAD electronics design package.

Here are the full KiCAD design files for this project, if you would like to make your own or use the ideas here.

Also, the Gerber files for the PCB are available here.