Original Message -----------------------
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.

------- Nick Veys wrote:

This seems like a nice simple solution, how critical is proximity=
 to the input pin for the low-pass network?  Should it be as=
 close as possible to the potentiometer to filter the input=
 sooner and a short PCB run to the input pin, or should it be as=
 close as possible to the input pin to eliminate any induced=
 interference on the PCB?

Should the grounds be isolated?

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