led drives and pwm

Forum 2005-2010 (read only) Hardware Interfacing
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This is my first post so be gentle if i have completely missed something.

I planning to make a controller for a led system.

The led system will comprise of about 60 3w cree leds powered by 10 luxdrive buck pucks which in turn will be controlled by the pwm on the arduino.

There is only going to be 2 channels one white and one blue.

So my question is what would be the best way to wire the control for the buckpucks using the least amount of the arduinos pwm pins,I was thinking of using an optocoupler so i could put 5 buckpucks to each pin. Is there a better way of doing this ?

This is a link to the buck puck BuckPuck 302xD - DC/DC Buck Driver - LEDdynamics

Thanks Adam

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So my question is what would be the best way to wire the control for the buckpucks using the least amount of the arduinos pwm pins,I was thinking of using an optocoupler so i could put 5 buckpucks to each pin.

You just need two PWM outputs one for each buckpuck. The input impedance is 1K so if you assume the Arduino can supply 40mA then you can drive 8 buckpucks from one pin, without the need for any optoisolation.