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Homework Help: Finding a start to simple preamp circuit (1 opamp)

  1. Nov 7, 2004 #1


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    http://www.littleboyinc.com/uploader/uploads/opamp.JPG [Broken]

    I searched all over to get some notes on how to handle opamp circuits like this with feedback, but nothing on when there's no resistor in series with the input source. Can anyone help me out on where to find examples? This sort of thing isn't covered in my text, and I just need a push to find equations to use.
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Nov 8, 2004 #2


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    All right, here's what I've got:

    Flo (low frequency of 50 Hz) = 1/(2pi*tau)

    I repeated for Fhi (2000 Hz).

    I solved for tau, which is some combination of C, R1, R2, and R3.

    Now that I have two time constants, how do I determine what the combination of C and R's to solve for?

    Thanks for the help so far, very much appreciated :)
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