Zin/zout for high-pass filter help?

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The discussion focuses on determining the input impedance (Zin) and output impedance (Zout) of a high-pass filter circuit in relation to frequency. The transfer function is given as Vout/Vin = R/(R + 1/jwC), with Zin identified as Xc = 1/jwC. There is uncertainty regarding Zout, with considerations that it may be R + Xc or just R, especially at high frequencies where the imaginary part becomes negligible. The importance of the circuit's configuration and the driving source's impedance is highlighted for accurately calculating Zout. Participants suggest calculating both Zin and Zout based on the provided circuit details for clarity.
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Homework Statement


An expression for Zin (impedance seen fromthe input) and Zout (impedance seen from the output) of the high-pass filter circuit with respect to frequency is: ?

The Attempt at a Solution


i have, bythe way, equation for transfer function already. Vout/Vin= R/(R+1/jwC). i am pretty sure Zin=Xc=1/jwC but not so sure about zout. would it be R+Xc or just R? i know at high frequency the imaginary part drops, so its just R.

or maybe i am doing this wrong. should i do the same thing for zout/zin as vout/vin?
 
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It would be much easier to help you if you would post a schematic of your filter circuit.
 
JqceA9e.png

it is typical high-pass filter circuit so i didnt think to post a pic. the Vin source was supposed to be 1vpk. the R value i calculated from the fc (cutoff freq) value =1.5kHz.
 
xhuang23 said:

Homework Statement


An expression for Zin (impedance seen fromthe input) and Zout (impedance seen from the output) of the high-pass filter circuit with respect to frequency is: ?

The Attempt at a Solution


i have, bythe way, equation for transfer function already. Vout/Vin= R/(R+1/jwC). i am pretty sure Zin=Xc=1/jwC but not so sure about zout. would it be R+Xc or just R? i know at high frequency the imaginary part drops, so its just R.

or maybe i am doing this wrong. should i do the same thing for zout/zin as vout/vin?

How do you get Zin=Xc=1/jwC? Zin is the impedance calculated at the Vin terminals. Isn't R1 part of that impedance?

Zout will depend on whether or not anything is connected to the Vin terminals. If the filter is driven by a voltage source (having zero ohms internal impedance), then Zout is the impedance seen at the Vout terminals with the Vin terminals shorted (by the impedance of the driving source).

Try calculating Zin and Zout with this information.
 

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