Folded Cascode Op-amp :
In order to overcome the drawbacks of telescopic cascode op-amp namely limited output swing, and difficulty in shorting the input and output a "folded cascode" op-amp can be used.
The idea of folding is that in a cascode differential amplifier the input
device is replaced by the opposite type while still converting the input
voltage to a current as shown in
An important property of folded cascode op-amps is the capability of handling input common mode levels close to one of the supply rails.