Low-voltage class AB buffers with quiescent current control

This paper presents a simple class AB buffer which is suitable for low-voltage (1.5 V) applications. The proposed buffer uses an adaptive load to reduce the sensitivity of the quiescent current to the process variation. The main feature of this scheme is its simplicity. The circuit was fabricated in a 2.0 μm digital CMOS process. Experimental results demonstrate that the buffer can operate with a supply voltage below 2 V, and it has the capability to drive small resistive loads