> Mosfets are perfectly good relay drivers in general. I can't tell wether
> you want them to be immune from noise, or you think that they create
> noise??  There is an impulse when you turn off the relay coil, but you can
> handle that in hardware, either with a snubber, or by turning the FET off
> slowly. It's the attempt to instantaneously stop the current through an
> inductor that gets you into trouble there.

Dave, I ask about using the FET INSTEAD of the relay, not to drive it.

The question is:
WHAT can I use to work like a switch for a signal that is not suposed to be
carring big current, but that can work properly without disturbing the rest
of the circuit (specially the PIC) if noise appears between the terminals;
for example: yesterday I tried the circuit with a machine that was suposed
to *close a path* for a relay in that machine, and SURPRISE!! I found a
*nice* 45Vac signal coming out of those terminals that were suposed NOT to
be there.

I'm looking for a SWITCH SUBSTITUTE that can carry this NOISES WITHOUT
disturbing the rest of the circuit.

Thanks for your answer. :)


Jaume.

----------------------
  Jaume Aragay Badia
   aragay@email.com
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