Mark E. Skeels wrote:
> No, it would work, but it's the power dissipation.
>
> It will see ~ 40 Amps at times. It sits on a heat sink.
>
> A quick check on Digikey for a 45A, 60V schottky shows a drop of 600
> mV.
>
> I'm pretty sure I can do better with a MOSFET, right?

Maybe.  600mV at 40A is 15mOhm.  You can probably find that in a FET, or get
it by paralleling two or more.

> So the FET does not turn on, and conduction occurs only through the
> body diode?

No.  As I said, that would be pointless.  If you're only going to use the
body diode, you might as well just use a real diode in the first place.
Then you can make the diode Schottky, which will drop less voltage.  The
only point in using the FET is to have it turn on during normal operation
with a on resistance low enough so that the voltage drop is lower than what
a diode would be.


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