Hello all,

First off I apologize if this is a simple question but I am not that great at circuit analysis and it has me stumped and I haven't been able to find a solution yet.

I have a butterworth high pass filter and I need to calculate the input impedance of it. I was wondering if there is a system or general method for analyzing these types of circuits. I have found resources to analyzing other op amp circuits but I have been having trouble extrapolating them to this problem.

Any guidance or help would be greatly appreciated.

Thank you,
Eric

http://imgur.com/hWapD (link to a image of the circuit, I apologize for the poor image I made it in paint)

 

Look at this thread
http://forum.allaboutcircuits.com/showthread.php?p=348387#post348387

 

Thank you very much! That is extremely helpful. I thought I did a good job searching for something like that, apparently not though. Sorry for the repeat question.

Thank you again,
Eric