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>> In this video, I would like to review what a non-inverting summer does.

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We begin by starting with a non-inverting amplifier that you see here,

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where you have a single input voltage going to a single output voltage.

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Then, we're just going to start adding input voltages to it.

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So, we've got this Rs2 with a second voltage Vs2.

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What happens over here is that this side acts somewhat like a voltage divider,

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and so we're going to have an additional gain term over here which is

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Rs2 over Rs2 plus Rs1,

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and then we're going to add in our second voltage Vs2 times Rs1 over Rs1 plus Rs2.

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This again right here is multiplied by both of them.

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This gives us a circuit that has positive,

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both of these are positive,

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this value is positive,

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this is positive, this is the non-inverting part that we

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have no change in the polarity or the positive-negative of our values.

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So, we could bring Vs1 and Vs2 into

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a circuit where we're going to multiply each of them by a separate value,

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a gain term, and then we're going to bring them

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together and add them up and that gives us the V out.

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This is what a non-inverting summer does.

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Remember that as with all of our op-amp circuits,

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the value of V out is still limited between

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the two power supply voltages Vcc and minus Vcc,

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we can't get any bigger or smaller than the

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power supplies that we're using, and there's our circuit.