Take an existing opamp design (e.g. hw4), and convert it to a fully differential output opamp with
common-mode feedback (CMFB).
Use an ideal voltage source (you choose the voltage) as the output common-mode voltage reference.
Specifications (fill in with your design results in the empty places)
Power supply 1.8V
Load 10pF (for each of the two output nodes to ground)
**Differential loop gain –
**Differential loop UGBW –
**Differential loop PM –
CMFB loop gain –
CMFB loop UGBW –
CMFB loop PM > 45°
Output CM accuracy/error < ±0.1V
Output swing –
Power consumption –
** Differential loop characteristics should be obtained with 1pF input and feedback capacitors.
You may use 1GΩ resistors for simulation as/where needed.
Eliminate the differential feedback (1pF capacitors) when doing CMFB evaluation.