Philip Pemberton wrote:
> 2) How can I keep the noise level in the sensor and amplifier to a
> minimum? Obviously I can average the A/D values in software, but I'd
> prefer to stop the noise being generated in the first place!
>=20
> Would it be worth adding a lowpass filter to the amplifier, or am I
> better off doing that in software (averaging)?

The noise at the output of the amplifier is going to be a function of
sensor noise, internal noise and bandwidth, so yes, limiting the bandwidth
of the amplifier to the minimum needed by the application will be a good
approach.

> 3) Is there anything else I should be aware of when designing something
> like this?

Input offset voltages and currents in the amplifier, and their temperature
stability.

Did you read the analog IC deisgn e-book that came through here recently?
Even if you're not going to design ICs, it provides a lot of insight into
the issues involved in using them.

-- Dave Tweed
--=20
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