过电平采样模数转换器误差源的建模  

Modeling Error Sources in Level Crossing Analog-to-Digital Converters

作　　者：金硕巍[1] 李晶皎[1] 苏瑞琴 李贞妮[1] JIN Shuo-wei;LI Jing-jiao;SU Rui-qin;LI Zhen-ni(School of Information Science&Engineering,Northeastern University,Shenyang 110819,China)

机构地区：[1]东北大学信息科学与工程学院,辽宁沈阳110819

出　　处：《东北大学学报（自然科学版）》2018年第4期478-482,共5页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金资助项目(61370153)

摘　　要：过电平模数转换器采用异步采样的方式进行数据转换.主要对转换器的不同时间模式进行了研究,综合分析了误差源对异步采样ADC性能的影响,特别对有限时间分辨率、有限精度量化两种主要误差源进行了详细分析.通过优化设计,将计算采样时刻的最大量化误差降为计数器时钟周期的一半,有效提高了系统的信噪比(SNR).推导出SNR的方程,对于固定的时钟频率,当量化分辨率较大时,SNR达到62 d B左右.通过仿真确认了方程的正确性.Level crossing analog-to-digital converter adopts asynchronous sampling method for data conversion.D ifferent tim ing schemes in asynchronous sampling ADC were studied,and the effect of main error sources on the asynchronous sampling ADC performance was analyzed,especially for the lim ited resolution of the tim er and the lim ited accuracy of the quantization levels.By optim izing the design,the maximum quantization error of the sampling time was reduced to half of the clock cycle,based on which the system SNR could be effectively im proved.The equation of SNR was presented,and when the quantization resolution was large enough,SNR could be about 62 dB for the fixed clock frequency.The correctness of the equation was confirmed by sim ulation.

关 键 词：过电平模数转换器 异步采样 有限分辨率 有限量化精度 信噪比 

分 类 号：TN43[电子电信—微电子学与固体电子学]