Self-Biased Dual-Path Push-Pull Output Buffer Amplifier for LCD Column Drivers

A high-performance buffer amplifier topology for liquid crystal display drivers is presented. The proposed amplifier achieves fast driving performance and offers a rail-to-rail common-mode input range. Enhanced slewing and settling capabilities are achieved through a novel output stage performing dual-path push-pull operation. No additional biasing network is required to set the quiescent conditions of the class-AB output stage, since the output static current is inherently controlled by the input differential stage itself, without additional power dissipation. Experimental results demonstrate that the suggested buffer can drive a 1000-pF capacitive load with a 5.7-V/μs slew-rate and a 0.71-μs settling time, while drawing 32-μA overall quiescent current from a 5-V power supply.