A very flexible BiCMOS low-voltage high-performance source follower

This paper presents a new high performance source follower, which features very low output impedance and excellent driving capability, while only requiring a supply of one threshold plus two saturation voltages. In fact, its output conductance can be increased by a factor>500 with a suitable local loop, making this cell suitable for driving loads up to some tenths of ohms. Using this basic black, a novel class AB push-pull operational amplifier has been designed. It achieves good performance (output quiescent current=1.2 μA, peak output current>200 μA, max. capacitive load=1 nF), with a supply voltage of 1.3 V and a total power consumption of only 3.7 μW