> The higher frequency case is interesting though. I have to admit that
> I can't quite visualize what is happening in terms of voltage drop
> and current flow during diode turn OFF that causes a high
> instantaneous peak power. (Assumption is that because turn-on time of
> a "slow" diode is the same as a fast diode, the extra power
> dissipation must be happening when the the diode turns off ie, when
> the inductive load is turned on gain). Can you explain?

        IIRC it deals with minority carrier storage effects. It takes a while for
the junction to "get rid of" the stored charge, during which time the diode
is conducting current, usually at many times the normal forward drop. For
more info pretty much any power electronics book covers it, I can't find the
text I often refer to right now. TTYL

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