I am new to the Arduino and electronics in general, so please excuse the simplicity of this question.
I am wanting to retrofit a desk lamp using 1 x Cree MC-E RGBW and control it from the iphone. I want to have control of each colour on the MC-E which is mounted on a star PCB board with each LED being individually addressable. I have the UNO and have been looking for an LED driver with 4 channels allowing for PWM control from the UNO. I found the Rainbowduino which has more channels than I require but it seems perfect otherwise.
I am not looking to reinventing the wheel on this project as far as the Led driver/controller goes hence being after some type of UNO compatible shield.
Are there many other options for 4 channel LED drivers available?
Rainbowduino only allows 20ma per channel. Your LED wants 350ma per channel.
A TLC5940 (google it) will allow 16 channels at 120ma each and you can group up three channels to meet your power requirements. It's an IC, not a shield, but wiring it up on a "protoshield" should be pretty straightforward.
High power leds like the CREE require/prefer a constant current source, that is not really provided by the traditional resitor in series with LED model. As a beginner you would be better served by looking for either a IC designed for those types of LED's or even better use an existing driver module.