用于TFT-LCD源驱动电路的面积节约型DAC

An Area-saving DAC for TFT-LCD Source Driving Circuit

提出一种用于TFT-LCD的新型数模转换器(DAC),详细地阐述了它的工作原理及其设计与实现。这种DAC与传统的电阻串DAC的结构完全不同,在传统DAC中电阻串是不可或缺的组成部分,而文章提出的DAC由计数器、比较器、传输门和其他组合电路组成,它克服了传统的电阻串DAC当输入数据位宽增加时所遇到的面积问题。用Spectre仿真的结果表明,该种结构DAC的转换精度完全满足高灰度等级TFT-LCD源驱动电路的设计需求。

A new type Digital-to-Analog Converter （DAC） for TFT- LCD source driver circuit is presented in this paper. The principle and implementation of the proposed DAC are illustrated. The proposed DAC is composed of counter, comparators, switches and other combinational circuits. This is completely different from the conventional DAC architecture, of which the resistor-string is an essential part. The proposed DAC can overcome the area problem that the conventional resistor-string DAC encounters when the width of input data increases. The Spectre simulation results show that the precision of proposed DAC meets the requirement of high gray scale TFT- LCD source driver.