Hi all,

I am designing a folded cascode OTA with gain boosting. I am trying to figure out the right topology for gain bost aplifier. I came across the paper from Bult 91 where he mention that it is necessary to have a additional stage with "input common mode range close to the supply voltage".

Then he goes on to suggest using folded cascode as the gain boosting amplifier. But I cannot figure out what he means by input common range and how does folded cascode help in that.

Any help will be great!


PS - I have attached the paper I am talking about. (Pg 8)