Difference Amp

For this lab we had to create a difference amplifier, and find the relationship between vin and vout. From our calculations we found that if both the Rin resistors are the same values. The relationship between Vin and Vout is

                                                  Vb-Va=Vout
Where Vb and Va are our input voltages.  It's called a difference amplifier because it outputs the difference of the input voltages.

Here's the circuit diagram


















Here's our circuit




















Here's our graphs
This is for Vb=1





















Our theoretical values didn't exactly match our experimental values. For example when Vb=1 and Va=-4 our Vout should've been 5, but we got 4.30. My reasoning for this, is because the resistors we used weren't exactly equal, so I'm assuming this created the difference between theory and experiment.

This is our graph and values for when Vb=-1


We noticed the same thing when our Vb was equal to -1 V. Our values didn't match up to our formula. I'm assuming again it's due to the resistors.

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