Is it possible to get a finite current gain using CS or CD configuration?

[iVenky]

We have current gain in BJT with configurations like CE and CC. Their counterpart in MOS, which are CS and CD, has infinite input impedance which means that the current gain is infinite. I don't want to use CG but only CS or CD. In that case, is it possible to get a current gain using CS and CD configurations? Consider everything to be ideal and independent of frequency.

Thanks in advance. :razz::razz:

 

[keith1200rs]

A current mirror can have current 'gain' i.e. unequal current in the input/output nets.

Keith

 

[erikl]

is it possible to get a current gain using CS and CD configurations?

Sure, if you allow for a resistor between the control and the common node ... there won't be much linearity in gain, however

 

[iVenky]

This doesn't happen in BJT where it's possible to have a current gain easily. Anyway I will CG in that case.

 

[checkmate]

And why would you want a less than ideal current gain?
Besides, a CG has a current gain of 1.