> I am only driving LED's. I have a 22 x 10 matric of 3mm LED's. The reason
I
> want to vary the voltage is to provide display dimming in the dark since
the
> unit is destined for my car.

You would be better off not varying the voltage, but using PWM instead.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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