Title :
A 10-Bit LCD Column Driver With Piecewise Linear Digital-to-Analog Converters
Author :
Lu, Chih-Wen ; Huang, Lung-Chien
Author_Institution :
Nat. Chi Nan Univ., Nantou
Abstract :
A 10-bit LCD column driver, consisting of piecewise linear digital to analog converters (DACs), is proposed. Piecewise linear compensation is utilized to reduce the die area and to increase the effective color depth. The data conversion is carried out by a resistor string type DAC (R-DAC) and a charge sharing DAC, which are used for the most significant bit and least significant bit data conversions, respectively. Gamma correction voltages are applied to the R-DAC to lit the inverse of the liquid crystal trans-mittance-voltage characteristic. The gamma correction can also be digitally fine-tuned in the timing controller or column drivers. A prototype 10-bit LCD column driver implemented in a 0.35-mum CMOS technology demonstrates that the settling time is within 3 mus and the average die size per channel is 0.063 mm2, smaller than those of column drivers based exclusively on R-DACs.
Keywords :
CMOS integrated circuits; digital-analogue conversion; driver circuits; liquid crystal displays; piecewise linear techniques; CMOS technology; LCD column driver; charge sharing DAC; charge sharing digital-to-analog converters; data conversion; gamma correction voltages; liquid crystal display; liquid crystal transmittance-voltage characteristic; piecewise linear compensation; piecewise linear digital-to-analog converters; resistor string type DAC; resistor string type digital-to-analog converters; size 0.35 mum; timing controller; word length 10 bit; Active matrix liquid crystal displays; Computer displays; Data conversion; Digital-analog conversion; Electrodes; Liquid crystal displays; Piecewise linear techniques; Resistors; Timing; Voltage; Column driver; LCD-TV; digital-to-analog converter (DAC);
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2007.914274
