A 10-bit DAC with offset-adjustable op-amp for LCD column driver applications

Abstract

This paper proposes a 10-bit digital-to-analog converter (DAC) consisting of a 6-bit resistive DAC (RDAC) and a 4-bit offset-adjustable op-amp for LCD column driver applications. The 6-bit RDAC selects only one voltage from the global resistor string before transmitting it to the op-amp. The op-amp implements 4-bit interpolation by adjusting the offset voltage. The maximal differential nonlinearity and integral nonlinearity of the proposed converter were measured at 0.8 LSB and 0.81 LSB, respectively, using 1LSB equal to 2 mV. The proposed 10-bit DAC occupies only 70 % of the space required for a conventional 8-bit RDAC.