> But if we are going complex, how about a bridge rectifier in series with
the
> lamp, and a FET or bipolar on the output of the bridge rectifier.

That also has the advantage of allowing higher efficiency by allowing higher
voltage.  Instead of 12V, you can use 20-50V DC.  Since the voltage drops
across the diodes will be the same but a smaller fraction of the overall
voltage, efficiency goes up.  Of course you have to trust your code to
always stay below a certain PWM on percentage, else poof!


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

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