Instrumentation Amplifier represented by a single op amp?

So I am working on a bigger circuit, and this bit is part of that bigger circuit. Basically in the circuit we have a simple op amp, which apparently represents an instrumentation amplifier. What confuses me is that in this instrumentation amplifier i have 2 different inputs and one goes to V+ and the other to V-.

What would be the output of this circuit? I was not given an exact instrumentation amp. circuit. But i know for general circuit : Vout = (V1- V2)(R2/R1)(1+(2R5)/Rg)) Could anyone help me with this question, please? to find the Vout, when the circuit is represented like this?

by muffintop94
June 04, 2020

Can you share the actual schematic you're working on? We don't have enough information to answer your question.

An instrumentation amplifier can be made from op-amps plus resistors, or you can buy one off-the-shelf as a single component like the Analog Devices AD8221. Take a look at this link for the datasheet. In addition to power supplies, it requires other inputs: a gain resistor, and a reference voltage.

by mrobbins
June 04, 2020

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