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Happy new year all!

I'm wondering how to correctly use the reference pin on an INA128 Instrumentation Amplifier. Is there a way to use this pin to eliminate negative voltages (i.e. do a voltage shift)?

Thanks again.

user1883691
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    Yes, you can do a voltage shift through InAmp's REF pin. A [very similar question](http://electronics.stackexchange.com/a/52626/7036) was posted today. – Nick Alexeev Jan 01 '13 at 04:14
  • Thanks, that's what I am looking for. In the schematic on the reference section, how would you add the decoupling cap and what value? – user1883691 Jan 01 '13 at 04:28
  • Using this pin wrong can kill your CMMR, so be a bit careful. – Scott Seidman Jan 01 '13 at 12:51

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The reference pin is exactly for level shifting the output. Note that it is best to use a low impedance source for this.An op amp as a unity gain buffer or other configuration should ideally drive this pin.

For decoupling take a look at the typical application circuit in the datasheet. It recommends a 0.1uF capacitor. Perhaps an extra 10uF capacitor would also be good.

Gustavo Litovsky
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