基于时延滤波的TI ADC采样时间失配校准算法  

A TI ADC Timing Mismatch Calibration Algorithm Based on Delay Filtering

作　　者：李睿[1] 唐鹤[1] 武锦[2] 郭轩 周磊[2] 季尔优 彭析竹 LI Rui;TANG He;WU Jin;GUO Xuan;ZHOU Lei;JI Eryou;PENG Xizhu(School of Electronic Science and Engineering,Univ.of Elec.Sci.and Technol.of China,Chengdu 610054,P.R.China;Institute of Microelectronics,Chinese Academy of Sciences,Beijing 100029,P.R.China)

机构地区：[1]电子科技大学电子科学与工程学院,成都610054 [2]中国科学院微电子研究所,北京100029

出　　处：《微电子学》2022年第2期253-259,共7页Microelectronics

基　　金：四川省科技计划资助项目(2020YFG0283,2020YFG0284,2020YFG0285)。

摘　　要：针对时间交织型模数转换器(TI ADC)子通道间的采样时间失配,提出了一种基于时延滤波的校准算法。该校准算法是一种纯片外校准算法,在片外进行FFT分析并重新拟合理想信号,提取每个子通道信号的时延偏差,再由此偏差计算每个子通道对应的FIR滤波器系数,完成时延偏差的补偿。该校准算法解决了子通道间采样时间失配导致的TI ADC精度不足的问题。将该算法应用于12 GS/s 12 bit ADC交织板。结果表明,无杂散动态范围(SFDR)平均提升了31.356 4 dBc,有效位数(ENOB)平均提升了3.177 6 bit。To solve the timing mismatch between time-interleaved ADC channels, a calibration algorithm based on delay filtering was proposed. This algorithm was a pure off-chip calibration algorithm. The delay deviation of each sub-channel was extracted by off-chip FFT analysis and refiting the ideal signal, then it calculated the corresponding FIR filter coefficient to compensate the delay deviation. The calibration algorithm solved the problem of insufficient precision of TI ADC caused by timing mismatch between sub-channels. The algorithm was applied to a 12 GS/s 12 bit ADC interleaving board. The results show that the mean increase of SFDR and ENOB was 31.356 4 dBc and 3.177 6 bit respectively.

关 键 词：时间交织型模数转换器 采样时间偏差校准 时延滤波 

分 类 号：TN792[电子电信—电路与系统]