Getting the sum and difference of two signals with op amps? SOLVED

I have two signals, one is a baseline voltage $V_{1}$ and the other is a difference voltage $V_{2}$. From these I want to produce two signals, $V_{1}$ + $V_{2}$ and $V_{1}$ + $V_{2}$. Is this possible?

by jkary
November 10, 2016

1 Answer

Answer by agiustino45

This is totally possible. Lets take the circuits one by one, looking this adder circuit first.

Notice how its just a voltage divider between the two inputs, plugged into an amplifier with a gain of 2. Go ahead and drop into the simulator and probe around the circuit. An interesting one to look at is the DC Sweep, that sweeps the voltage of V2 from 0-5 linearly, and you can verify that $V_{out}$ is always $V_{1} + V_{2}$

Now take a look at the difference circuit below that calculates $V_{out} = V_{1} - V_{2}$

You can use unity gain buffers to hook these two up to your two inputs.

ACCEPTED +2 votes
by agiustino45
November 10, 2016

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