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Circuit From Transfer Function

  1. Feb 24, 2013 #1
    I'm given the following transfer function:
    [tex]T(s)=\frac{50000s}{(s+50)(s+1000)}[/tex]
    and I need to constuct a circuit from it using opamps, resistors, capacitors, and inductors. Capacitors must be 100nF.

    I'm not quite sure how to start here. I managed to get a time domain version of the transfer function:
    [tex]T(t)=\frac{-50000}{19}e^{-50t}+\frac{100000}{19}e^{-1000t}[/tex]

    The problem is I have no idea how to get started. I know that the time function looks like a capacitor discharging, however I don't know how to start going about turning this function into a circuit.
     
  2. jcsd
  3. Feb 24, 2013 #2

    gneill

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    Staff: Mentor

    You should familiarize yourself with the transfer functions of the simple RC filters (low pass and high pass).

    hint: An op-amp can be used as a buffer between filter stages (keeps them from interfering with each others corner frequencies and gains).
     
  4. Feb 24, 2013 #3
    Ah, I see. So I can separate it into two systems with the following characteristics:

    [tex]H_{1}=\frac{50000}{s+50} H_{2}=\frac{s}{s+1000}[/tex]

    and buffer them together?
     
  5. Feb 24, 2013 #4

    gneill

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    Staff: Mentor

    Yes, you could.
     
  6. Feb 24, 2013 #5
    Or I could interchange the numerators. Either way this puts me on a better track, I'll see what I can come up with.
     
  7. Feb 26, 2013 #6
    I managed to solve it! Thanks for pointing me in the right direction.
     
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