>
> Also, you may need to pay some attention to the ground return current to
> make
> sure it isn't getting into other stuff. The problem is actually worse with
> MOSFETs because they tend to switch much faster, and a teeny bit of
> inductance
> can lead to failures.
>
>>Best regards,
>
> Spehro Pefhany --"it's the network..."            "The Journey is the
> reward"


I had fun blowing out a lot of high voltage high current FETs a few years
ago. The problem turned out to be inductance in the source lead. A fast
current change caused the source voltage to vary with respect to the gate,
exceeding the Vgs voltage rating. A resistor in series with the gate
(slowing the FET down a little) solved the problem by allowing the Cgs to
get the gate to "follow" the varying source voltage, keeping Vgs from
getting too high.

Harold



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