I have an application where I'm considering just using the voltage drop=20
produced by Rds(on) across a FQB22P10 fet in the place of a current=20
sense resistor.   This is one of those applications where the exact=20
current draw is not really needed, but instead it is more being used as=20
a 'load present' detection.   The load is actually around 0.5A - which=20
based on the just under 0.1 Ohm Rds(on) resistance, I'm right where I=20
need to be for my 20V/V current sense amplifier....

Whenever I consider something like this, I worry that I've missed some=20
critical piece of 'semiconductor physics' which would make this not work.

Is there a reason I shouldn't do this, or why I wouldn't get at least=20
somewhat accurate results?

-forrest
--=20
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