A 10-Bit Column-Driver IC With Parasitic-Insensitive Iterative Charge-Sharing Based Capacitor-String Interpolation for Mobile Active-Matrix LCDs Hyun-Sik Kim, Student Member , IEEE, Jun-Hyeok Y ang, Sang-Hui Park , Student Member , IEEE

Abstract

This paper presents a 10-bit column driver IC for active-matrix LCDs, with a propos ed iterative charge-sharing based (ICSB) capacitor-string that interpolates two output volt- ages from a resistor-string DAC. Iterative mode change between a capacitive voltage division mo de and a charge sharing mode in the ICSB capacitor-string inter polation suppresses the effect of mismatches between capacitors and that of parasitic capacitances; thus, a highly linear capacitor sub-DAC is realized. In addition, the area-sharing layout technique , which stacks the interpolation capacitor-string on top of the R-DAC area, reduces the driver channel size and extends the bit resolution of the gamma-cor- rected nonlinear main R-DAC. Consequently, the proposed ICSB capacitor-string interpolation scheme provides highly uniform channel performance by passivel y dividing the coarse voltages from the global resistor-string DAC with high area ef ficiency, and more effective bit resolution for nonlinear gamma correction. The prototype column driver IC was implemented using a 0.11-µm CMOS process. The area occupation of the DAC and buffer amplifier per channel is only 188 × 15 µm 2, and the static power consumption is 0.9 µA/channel with no additional static power dissipation for the interpola tion. The measured maximum DNL and INL are 0.25 LSB and 0.43 LSB, respectively. The measured maximum inter-channel DVO is 5.6 mV. The proposed chip achieves state-of-the-art perfo rmance in terms of chip size and ch