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

• Published in: IEEE transactions on circuits and systems. II, Express briefs Vol. 65; no. 12; pp. 1879 - 1883
• Main Authors: Grasso, A. D., Palumbo, G., Pennisi, S.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.12.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Amplifiers; buffer amplifier; Buffers; Circuits; class AB; CMOS; CMOS technology; column drivers; Current measurement; Diving; Figure of merit; Flat panel displays; High speed rail; Liquid crystal display; Rail to rail amplifiers; rail-to-rail; Semiconductor devices; settling time; Simulation; State of the art; Threshold voltage; Transistors
• DOI: 10.1109/TCSII.2018.2817261
• ISSN: 1549-7747

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-<inline-formula> <tex-math notation="LaTeX">{\mu }{\text{m}} </tex-math></inline-formula> technology and supplied from a 3-V supply, the proposed buffer amplifier can drive a 1-nF column line load within a 1.11-<inline-formula> <tex-math notation="LaTeX">{\mu }\text{s} </tex-math></inline-formula> settling time under a full voltage swing, while drawing only 1.6 <inline-formula> <tex-math notation="LaTeX">{\mu }\text{A} </tex-math></inline-formula> quiescent current and occupying 5562 <inline-formula> <tex-math notation="LaTeX">{\mu }{\text{m}}^{{2}} </tex-math></inline-formula> of silicon area. As compared to the state of the art, the best figure of merit (pF/<inline-formula> <tex-math notation="LaTeX">{\mu }\text{s}{\cdot } {\mu }\text{A} </tex-math></inline-formula>) is found.