On-Panel Output Buffer With Offset Compensation Technique for Data Driver in LTPS Technology

Abstract

To overcome the offset voltage (V(OS)) of output buffer due to large variation on characteristics of thin-film transistor (TFT) in low-temperature polysilicon (LTPS) technology, a class-B output buffer with offset compensation circuit for the data driver is presented in this paper. This proposed class-B output buffer can operate at 50-kHz operation frequency with a 2-8-V output swing for extended graphic array (XGA) application, and it has been demonstrated in 3-mu m LTPS technology. Using the offset compensation technique, the V(OS) of output buffer can be controlled within +/- 100 mV under 2-to-8 V signal operation to achieve a high resolution and quality liquid crystal display (LCD) panel.