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RGB LED interface with arduino

I need to drive 5 3W RGB LEDs in series using an arduino. The maximum current required is 350mA each for R G and B dyes.
and minimum current requirement is 2.4V, 2.4V and 3.5V respectively.

What should I use to interface the LEDs with my arduino as the output current of each arduino pin is 50mA maximum

Thanks in advance

nomuse9 months ago

The brute-force version is to switch the LEDs with power darlingtons, and stick a hefty half-watt ballast resistor on each LED.

A better solution is to use a constant-current regulator. There's a cheap regulator made for HR-16 lighting fixtures, based around the PT4115 chip; you can find those cheap at the discount suppliers: http://dx.com/p/internal-constant-current-source-p...

The cute thing about these is, the PT4115 has a PWM pin (not used in the cheap constant-current drivers). You can solder a whisker to that and you've got your LEDs.

I'd also caution that the Arduino's power supply won't want to do this kind of heavy lifting either.

mpilchfamily9 months ago

You will need a driver board for each LED.