Basic gain boosting topology(version 1): We have to analyze the output swing of this topology, the upper bound of the swing is limited by the current source overdrive voltage, if we want to stabilize the current source, we have to trade swing for current stability(the low voltage current source needs two overdrive voltage, but can stabilize current drastically). The lower bound of the swing can be extended by utilizing a folded cascode stage(to avoid headroom limitation)
Gain boosting topology with low voltage mirror(version 1.1): The current source of the circuit is implemented by low voltage cascode current mirror. From our simulation, we know that this circuit has a dramatical amplifying scale(about 13805.97), so the input DC level shall be very stable, which makes the circuit sensitive to fluctuation, so we need to design the biasing circuit carefully to make the circuit reliable.
The third edition compares the basic cascode topology with the gain boosting topology
