Thus spake Clyde Smith-Stubbs (clyde@HTSOFT.COM):

> Thus spake Martin Larran (fuglisi@UNSA.EDU.AR):
>
> > for the A/D. As I use a symethrical(12,-12) PS for the Op. Amp. of the
> > sensors,
> > if something goes wrong with some sensor(like wire breaks), the Op.Amp
> > will
> > saturate blowing the A/D. So which is the best way to prevent this?
>
> What about just using a series resistor for current limiting and a pair
> of clamp diodes to GND and VCC? The series resistor should not affect

Actually, looking at the 16C71 spec again, a simple series resistor of
2.2K or so should be quite adequate. The A/D inputs do have clamp diodes, and
the clamp current is specified as a maximum of +/-20mA.

--
Clyde Smith-Stubbs    | HI-TECH Software,       | Voice: +61 7 3354 2411
clyde@htsoft.com      | P.O. Box 103, Alderley, | Fax:   +61 7 3354 2422
http://www.htsoft.com | QLD, 4051, AUSTRALIA.   |
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