摘要
跟随器是CSTN-LCD系统中的关键模块,对提高系统的显示质量、改善系统的串扰具有决定性的作用。提出了一种CSTN-LCD驱动芯片中跟随器的实现方案:电路采用共源共栅频率补偿保证良好的频率响应特性,提高了对电源和地的抖动的抑制比;并引入浮栅电流源为AB类输出级提供偏置电流,使得电路结构更紧凑。基于GSMC±9V的0.18μm CMOS高压工艺SPICE模型进行了仿真分析,结果表明:去掉1μF外接电容,增益带宽积为350kHz,相位余度86°;在1MHz处PSRR+/-均大于-30dB。流片验证与测试结果表明:跟随器的电路面积小于600×100μm2;且在没有1μF外接电容下也能满足CSTN-LCD的高性能要求。
Fonower is the key module in CSTN-LCD. And it plays a crucial role in improving the display quality and erosstalk of CSTN- LCD system. In this paper, the implementation of the follower for CSTN- LCD Applications is presented. Moreover, cascade frequency compensation is used to obtain better frequency response properties and improve the PSRR of the circuit. And the floating current source providing bias current of A - B class output stage is introduced to realize a compact circuit structure. Base on SPICE model of GSMC ＋ 9V 0.18μm CMOS high - voltage process, simulation analysis indicates the operation amplifier has a unity gain bandwidth of 350kHz and phase margin of 86°without 1μF external capacitor. The PSRR ＋ / - are greater than - 30dB at 1MHz.Tape- out verification shows the area of follower is less than 600 × 100μm2 and it can meet the CSTN - LED requirements of high performance without 1μF capacitor.
出处
《茂名学院学报》
2010年第1期26-28,31,共4页
Journal of Maoming College
