> The best PWM frequency is usually the highest frequency you can afford
> when you consider the efficiency of any chokes or coils you use the PWM
> voltage on (they have a maximum efficiency rated frequency). Also because
> high frequency requires lower value filter capacitors and inductors for
> the same smoothing, and the design should be cheaper like this.

Peter,

I don't disagree with you, but I have a question.  Don't FET's generate most
of their internal heating during the transition phase (turning off or
turning on, just not quite all the way on or off yet).  If so, wouldn't this
make a case for a lower PWM frequency?

michael brown

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