采用新型动态器件匹配算法的高速数模转换器  

A High-Speed D/A Converter Using New DEM Algorithm

作　　者：程扬[1] 

机构地区：[1]中国科学技术大学计算机科学与技术学院,合肥230037

出　　处：《微电子学》2014年第1期6-9,13,共5页Microelectronics

摘　　要：采用5+7的分段方式,设计了一种12位1GHz电流舵数模转换器(DAC),分析了电流源版图误差对DAC性能的影响。为了抵消DAC版图的梯度失配误差,提出一种新型随机增减动态元件匹配(DEM)算法,并将其加入到高5位温度计码中,以优化DAC的动态性能。基于TSMC0.18μm CMOS工艺,完成了整个DAC的电路设计,并与常规DEM算法进行仿真比较,结果显示,在输入数据频率分别为10MHz和120MHz时,该DAC的无杂散动态范围(SFDR)分别提升7.2dB和3.8dB。A 12-bit 1 GHz currenvsteering D/A converter with 5＋7 segments was designed. Effects of layout mismatch on performance of the DAC were analyzed. A new random-plus-minus dynamic element matching （DEM） algorithm was added to the upper 5-bit thermometer codes to cancel gradient mismatch error and optimize dynamic performance of the DAC. The circuit was designed based on TSMC＇s 0. 18 μm CMOS process. Simulation restllts showed that the SFDR of the DAC was improved by 7. 2 dB and 3. 8 dB at signal frequencies of 10 MHz and 120 MHz, respectively.

关 键 词：数模转换器 电流舵 动态元件匹配算法 梯度失配误差 

分 类 号：TN792[电子电信—电路与系统]