Finding Thevenin equivalent in the S domain

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Lancelot59
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I'm given the circuit in the attached image (I just quickly re-created the circuit in LTSpice to save on drawing time).

In the first part of the question I managed to find the S domain transfer function without any issue. I found the transfer function as some function of the resistors, capacitors, and S.

Now however I need to find the thevenin equivalent at the point V2(t), and I'm not quite sure how to get started with this working in the S domain.
 
Attachments
  • Circuit schematic: voltage source V1(t) feeds node V1 through capacitor C1 to a middle node, then through capacitor C2 to output V2(t); resistor R1 runs from the middle node to ground, and resistor R2 runs from the input node over the top to the output node.
    Untitled.png
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Simon Bridge said:
But there is a short circuit across those nodes!

Anyway - do you know how to find impedences in the s-domain?
Try: http://www.engr.mun.ca/~egill/index_files/unit5382106.pdf p22
(diagrams didn;t come out for me - but you can see the method without them)
Maybe: http://www.stanford.edu/~boyd/ee102/laplace_ckts.pdf

Oops, I left a connection in by accident. Ignore the short. Finding the impedances was easy enough, and like I said I found the transfer function.

A thought occurred to me. Isn't this going to wind up being the equivalent series impedance, in series with a voltage source that is the the transfer function?
 
You can find ##V_{AB}## - a bit more care is needed for the input impedance.
Just go through the normal steps for finding the equivalent circuit. You should be able to satisfy yourself about the validity if you keep in mind what the various bits of math mean.