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RC Op Amp phase shifter transfer function/how to get

  1. Nov 28, 2013 #1

    I am trying to figure out the transfer function for an RC phase shifter:
    http://imgur.com/2dnRYn7 (Picture of circuit)

    I am not sure how to calculate the output and specifically the phase of the output of this circuit. I understand that I need to consider one of the 'golden rules' of ideal op amps that v+ = v- but I'm unsure of how to consider the voltage going in to v+. My knowledge in this area is pretty shaky!

    I understand that I cannot just be supplied with the output/phase equation of this circuit and don't want it, but would like some help figuring it out! Can anyone help push me in the right direction?

    Thanks for reading.
  2. jcsd
  3. Nov 28, 2013 #2
    Simply treat RC as a voltage divider.
    v+ = Vin * Xc/(R + Xc) or Vin = (1/s*C)//(1/s*C + R)
    Last edited: Nov 28, 2013
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