At 10:50 AM 1/7/03 +1300, Brent Brown wrote:

>Don't forget the protection diode like Jinx says, or use a zener. Put
>the diode after the R of the RC filter so the diode current will be
>limited.

Using a Schottky diode is not a good idea if you place it after the series
resistor - the leakage current is too high.  However, I have found that I
have NEVER needed the diode in the arrangement described - 3 wires off to
the pot, low pass RC network feeding the a/d input.

I do this in some very high noise environments without problems.

dwayne

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Dwayne Reid   <dwayner@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
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