Dual Push-Pull High-Speed Rail-to-Rail CMOS Buffer Amplifier for Flat-Panel Displays

This brief presents the experimental validation of a low-power, large output swing, class-AB buffer amplifier for column drivers of active-matrix flat-panel displays. By exploiting two complementary input amplifiers and a dual-path push-pull output stage, the proposed circuit achieves high-drive performance and rail-to-rail operation. In addition, two current boosters allow area optimization of the output diving transistors by dynamically lowering their threshold voltage. Implemented in a standard triple-well CMOS 0.35-mu m technology and supplied from a 3-V supply, the proposed buffer amplifier can drive a 1-nF column line load within a 1.11-mu s settling time under a full voltage swing, while drawing only 1.6 mu A quiescent current and occupying 5562 mu m(2) of silicon area. As compared to the state of the art, the best figure of merit (pF/mu s center dot mu A) is found.