What is the maximum gain for a single stage OTA ?

[safwatonline]

max. gain

hello,
i was wondering
1-what is the max. gain for a single stage OTA,
2-and whether if this gain always increase with increasing the tail current (gm=2I/Veff)? ,
3-also when do i say this stage is not enough ,(i.e. i got max. use of it and i need another stage).
thnx.

 

[eng_Semi]

Re: max. gain

for a self biased single stage OTA, the maximum gain is about 50dB. As the tail current inc, gm inc but ro dec so the gain isn't increase

But u can reach a 60dB gain or higher using a folded cascode or a telescopic cascode OTAs