A small-area and low-power data driver IC using two-stage DAC with a capacitor array for active matrix flat-panel displays

Abstract

A small-area and low-power data driver integrated circuit (IC) using a two-stage digital-to-analog converter (DAC) with a capacitor array is proposed for active matrix flat-panel displays. The proposed data driver IC employs a capacitor array in the two-stage DAC so as to reduce the DAC area and eliminate the need for a resistor string, which has high-power consumption. To verify the proposed two-stage DAC, a 20-channel data driver IC with the proposed 10-bit two-stage DAC was fabricated using a 0.18-m complementary metal-oxide-semiconductor process with 1.8 and 6V complementary metal-oxide-semiconductor devices. The proposed 10-bit two-stage DAC occupies only 43.8% of the area of a conventional 10-bit two-stage DAC. The measurement results show that the differential nonlinearity and integral nonlinearity are +0.58/-0.52 least significant bit and +0.62/-0.59 least significant bit, respectively. The measured interchannel deviation of the voltage outputs is 8.8mV, and the measured power consumption of the 20-channel data driver IC is reduced to 7.1mW, which is less than half of the power consumed by the conventional one.