Double stage op-amp + control circuit.
A "Cannot find solution" message may appear (I think EC has some difficulties when feedback is involved): just set the voltage source in the bottom right corner (3V default) to low values (1V) (feedback reset) and then bring it up to ~3V. This voltage source controls the common output voltage of the differential stage which would be hard to set manually because of the active loads (a second differential stage is used to achieve this). By changing it (within the saturation range of the MOSfets [2.8 - 3.4]) the blue and orange curves shift.
Gain ~160 (output, red curve).
If anyone knows why "Cannot find solution" message appears please comment!
