>I've got some FETs, in particualar a MIC94053, that I am driving from a PIC
>by tristating it to turn it off, and drive it low to turn it on.  It has a
>built in PUP, and with 3.3V on the source I am seeing around .8 to .9 V on
>the drain.  I'm going to be doing some experiments and measurements  but I
>am posing the question right now...is this normal to see leakage like this?

I can't seem to find the datasheet for that particular part...Is it an
NFET or PFET?

It also sounds to me like you have it backwards...Shouldn't you be
trying to pull Vgs towards Vs to shut it off, instead of pulling Vds
towards Vd?  If it's a 3 terminal NMOS device, the substrate will
be internally connected to the source terminal, so what you're
describing won't work very well.  Of course, this is assuming you're
using an NMOS enhancement mode device, which may be a big
assumption, but they seem to be quite common.

If the last paragraph didn't make sense to you, grab your copy of
"The Art of Electronics" (you do have one, don't you?) and read
chapter 3.  Twice.

Mike H.

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