My first time posting, though I browse the forum occasionally...

I have an analog circuit attached as a .jpg file. I need to find the input impedance, but really have no idea where to start. If anyone could give me some pointers I would appreciate it, thanks.

 

The impedance would simply be the voltage across the i(in) current source divided by i(in). Define v(in) to be the voltage across i(in) and the impedance is v(in)/i(in). So all you need to do is come up with an expression for v(in).

- Tom Gootee

http://www.fullnet.com/~tomg/index.html