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JJBladester
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Homework Statement
The following voltages are applied to the instrumentation amplifier in the figure.
Vin1=5 mV, Vin2=10 mV, and Vcm=225 mV. Determine the final output voltage.
Homework Equations
[tex]R_{1}=R_{2}=R[/tex]
[tex]A_{cl}=1+\frac{2R}{R_{G}}[/tex]
[tex]V_{out}=\left ( 1+\frac{2R}{R_{G}} \right )\left ( V_{in2}-V_{in1} \right )[/tex]
The Attempt at a Solution
This is an odd-numbered problem in the back of my book, so I know the answer should be 1.005 V.
I already know my initial answer (see below) is wrong because it comes out to 1 V and does not take into account Vcm. Since I'm given Vcm but not Acm, CMRR, or anything else, how do I solve this problem?
Incorrect:
[tex]V_{out}=\left ( 1+\frac{2\cdot 100k\Omega }{1.0k\Omega} \right )\left ( 10mV-5mV \right )=1mV[/tex]