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Homework Statement
The op amp has a near ideal level 1 model with G = 5000V/V, ri = inf, ro = 0
How would I obtain the feedback function?
Homework Equations
I know I have to find the feedback function which is:
f =  (ΔV/Vin)
The Attempt at a Solution
I will first drive using the voltage source. My professor said to convert the op amp into a voltage source and short the nodes 1 and 2. He then said to find the feedback function by first finding ΔV = Vp  Vn which he gives (in the solutions) to be (R1 + R3)/(R1 +R2 +R3 +R4). How did he find this value for ΔV? I can try using the standard way of solving ideal op amps and resulting in two equations:
1: (VinVp)/R3  Vp/R4 = Ip
2: (VinVn)/R1 + (Vo  Vn)/R2 = In
and then I can solve for Vp and Vn but I do not get the same as he does. I get a value with In, Ip, Vo which he does not have. He only has resistance values in his ΔV. Any help would be appreciated. P.S. Since this is not ideal then I cannot use Vp = Vn and Ip = In = 0 right? thanks
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