Current Mirror Zeros

[George Sarris]

Hi all,
Can someone please explain me where do the zeros of a current mirror come from, intiutively? For the simplest current mirror, say with 1:1 ratio, we have a pole that is given by gm/2Cgs. There is a zero at double the frequency.. Can someone explain how can i view it in terms of parallel transfer paths? Thank you in advance.
Regards,
Georgios

 

[Dominik Przyborowski]

by calculate current gain for simple 2 transistor mirror.

 

[arya.jagadeesh]

in any circuit zero comes when there are two paths between same nodes with 180degree phase shift...in case of current mirror gate and drain are externally shorted so one path with no phase shift...and other is due to mosfet action ..gate and drain are 180 degree ...so these two paths give you zero and every node gives you one pole...ultimately u will get one pole and one zero..