Arduino controled led driver

Hi everyone. I would like to experiment with some cheap ebay led's for lighting while working on vehicles. The Idea is to have a 4ch variable current supply in the heart of the system. That way I can use 4 different led's say spots, floods and strips to light up the work area. I will need to be able to adjust the current on each channel, probably up to about 10W each channel at the high end.

The system will be powered by a 12V input. I'm not going to have any step up circuitry, so If it get's limited by the voltage before reaching full current that will be fine for what I need.

I'm not too sure on how to read the current and send it to the the arduino. Just looking around I came across the max471 chip. It seems really easy to use and has a inbuilt shunt, making it very simple. I was thinking if I use this to monitor the current, and then just write some code to vary the pwm output of a fet, use a lc filter to smooth it, it should work.

Would this be a good idea, or is there a better way to go about varying the current to a load with a arduino? Could anyone suggest a chip for current monitoring?

Thanks, David.

When dimming LEDs you usually don’t vary the LED current.
You just switch the LEDs on/off very fast, so humans think they look dimmed.
PWM dimming is just varying the on/off times.
Just get a constant current LED driver (fixed current), and PWM it.
Leo…