> Can you send the circuit (ASCII art) or put it on a website somewhere. It
> sounds a bit as if the input resistances to the opamp + and - terminals are
> different and a change in bias current with temperature is giving you an
> offset. - Otherwise the input offset voltage may be changing with
> temperature and you may need to go to a better opamp or provide external
> compensation. (I don't know the specs of the CA3130 opamp sorry)

Yes, that should be the first thing to look at. Also the pressure
transducer might not be temperature compensated.

Cheerful regards,

Bob

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