op amp inverting summer or adder

This is a super short video on the functional use of an op amp inverting summer (adder) circuit. More detailed info is available at www.ece.utah.edu/~ece1250

>> Now, let's review what an inverting summer does.

We can start with the inverting amplifier shown here and then add on

an additional voltage source, which has its own resistance and its own voltage.

Then, what's going to happen is Vo is going to be the combination of

these two voltages, as shown here.

As with all of our op-amp circuits,

the Vo is limited between the two power supply voltages as always.

We can look at this circuit as having two separate gains A and B,

or minus A and minus B.

And then, what we do is bring in Vs1 and multiply it by minus A,

bring in Vs2 and multiply that by minus B,

and bring the two of these together and add them,

that's the summer part.

That gives us V out.

So, that's how an inverting summer works.