Low-power dual-active class-AB buffer amplifier with self-biasing network for LCD column drivers

This work addresses a new compact low-power highspeed output buffer amplifier topology for large-size LCD applications. The suggested buffer achieves fast driving performance, draws a low quiescent current during static operation and offers a rail-to-rail common-mode input range. The circuit provides enhanced slewing capabilities by exploiting the push-pull output sections of two basic complementary-type input amplifiers to realize a dual-path push-pull operation of the output stage. An auxiliary bias network integrated in the input differential stage allows the quiescent conditions of the class-AB output stage to be inherently controlled without additional power dissipation. Post-layout results confirm that the proposed amplifier can drive a 1-nF capacitive load within a 0.9-μs settling time under a 3-V full voltage swing, while drawing only 3.5-μA quiescent current.