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Homework Help: Transfer Function

  1. Nov 24, 2011 #1
    1. The problem statement, all variables and given/known data

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

    2. Relevant equations

    3. 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?

    Attached Files:

  2. jcsd
  3. Nov 24, 2011 #2


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    Staff: Mentor

    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?
  4. Nov 24, 2011 #3
    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 thats right. I know the answer (it is at the top of the sheet). Here is what I have so far now.

    Attached Files:

  5. Nov 25, 2011 #4
    I got it :) Thx anyhow! Little bit of patience and practice pays off
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