Finding transfer function of RC circuit with op-amp

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triden
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Homework Statement



I need help finding the transfer function for the attached image.

Homework Equations

The Attempt at a Solution



I combined the 1/6F cap and the 1 ohm resistor into a single impedence. I know the AV of the opamp is -0.5/(6s+1). After that I am stumped.

Is there a name of this specific circuit?
 
Attachments
  • Circuit schematic labeled Figure P4.4-9 of an op-amp feedback network with input source v(t) and output y(t), containing resistors of 1 ohm, 1 ohm and 1/2 ohm and capacitors of 1/6 F and 1/3 F.
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Have you tried nodal analysis? Call node "a" the junction of the input 1Ω resistor and the capacitors, call node "b" the inverting input of the op-amp. The output of the op-amp can be Vo, while the circuit input signal is Vi. Remember the properties of an op-amp; there's a negative feedback loop, so what can you say about the voltage at the input terminals? How about the current?
 
Ok, I know I am on the right track. I have tried a couple things, but didn';t quite get it. I guess my problem is relating V- to V+. I want to think that V- = V+ = 0, but I don't think that's right. I know the answer (it is at the top of the sheet). Here is what I have so far now.
 
Attachments
  • Handwritten notes with a circuit schematic of an op-amp RC network driven by x(t), with resistors of 1 and 1/2 ohm and capacitors of 1/3 F and 1/6 F, and node labels Vin, Vx, V- and Vout; below are node equations for Vx and V- and the transfer function H(s) = -s / (s^2 + 8s + 12) written at the top.
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I got it :) Thx anyhow! Little bit of patience and practice pays off