One Quiescent Current and Chip Area Efficient Architecture of TFT-LCD Source Driver for Portable Applications

摘要

One architecture of 262K-colors TFT-LCD source driver efficient in chip dimension and static current, which is suitable for QCIF + (176RGB × 240) resolutions, is proposed in this paper. And it can be used in the mobile phone or the highend portable in practical. The conventional three type source drivers demand larger numbers of OPAMP buffers to drive the panel's pixels, and involve higher resistance value of R-DAC to generate gamma voltages for keeping the lowest static current, In this fourth type source driver, it only uses two OPAMPs and the lower resistance value of R-DAC without increasing the quiescent current. Thus, the source driver can save more area to increase the chip competitive advantages and reduce static power dissipation for extending the battery lifetime. The proposed prototype chip of the OP AMP and the 262 Kcolors TFT-LCD source driver were implemented by 3.3 V 0.35 μm CMOS fabrication technology. The circuit core size of the OPAMP is about 100 μn × 50 μm and the source driver is around 400 μm × 650 μm. The reduced chip area is approximately 54.25% and the wasted static current is around 2.6% by this forth architecture.