On Sun, 24 Apr 2016 13:32:39 -0400
Jason White <whitewaterssoftwareinfo@gmail.com> wrote:

> (1) A 2N7002 often is rated for a "typical" Drain-Source leakage current =
of
> 1 micro-amp when 60 volts is across it a room temperature. Will this
> leakage current decrease if the applied voltage is lower?
>=20
> (1b) Is it possible to extrapolate how much lower the current would be at=
 a
> lower Vds voltage?

Not really - and surely it's not linear. I also believe that the 1uA is
very probably an extreme value, probably at the max temperature, etc.
'Normal" transistors will be very much lower... But it would be unwise to
rely on that...

> (2) Would placing multiple MOSFETs in series reduce the Drain-Source
> leakage current? (Of course, then gate leakage current may start becoming=
 a
> factor.)

Placing several FETs in series will  reduce the leakage current somewhat,
but mainly because the voltage is reduced. But it'll introduce other
problems - you'd have to distribute the voltage evenly, which would=20
involve resistors, just what you don't want. And you'll increase the Ron.

Ever consider analog switches? The old CD4066 can switch 15 V, and has a
rating of 0.1nA Typ., at 25=B0C. A slightly more sophisticated switch
will surely do much better.

John

--=20
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