Electronic – Instrumentation amplifier

instrumentation-amplifieroperational-amplifier

I am using an instrumentation amp (http://www.linear.com/product/LT1168), and I am a bit confused why it is giving me a output voltage that I am not expecting.

I am pretty sure, I am doing something dumb here.

The way I have it hooked up now is as follows:

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I am expecting a 5V difference between the reference and the OUT pin, but I am only getting 3.9. What am I doing wrong here? I know the output will not go to the ramp voltage, but 3.9 seems too little.

There must be something I am missing.
Datasheet: here

Best Answer

The LT1168 does not have rail-to-rail outputs.

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