An ISI Scrambling Technique for Dynamic Element Matching Current-Steering DACs
An ISI Scrambling Technique for Dynamic Element Matching Current-Steering DACs
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DOI：
10.1109/jssc.2021.3085587
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发表时间：
2021-07
影响因子：
5.4
通讯作者：
Jason Remple;A. Panigada;I. Galton
中科院分区：
文献类型：
--
作者：
Jason Remple;A. Panigada;I. Galton
高分辨率电流舵型数模转换器(DAC)的线性度经常受到符号间干扰(ISI)的限制。虽然动态元素匹配(DEM)可以将部分ISI转换为不相关噪声而不是非线性失真，但DEM本身并不能阻止ISI至少引入强烈的二阶非线性失真。本文通过提出、分析和实验演示了一种称为ISI加扰的低成本附加技术来解决这个问题，该技术与DEM相结合，使得DAC的ISI没有非线性失真。码间干扰加扰技术在一个采用90 nm工艺实现的14位1-GS/S DEM DAC中得到了演示。该数模转换器的测量线性度符合最新水平，其输出功率谱与本文理论结果预测的值非常接近。
The linearity of high-resolution current-steering digital-to-analog converters (DACs) is often limited by inter-symbol interference (ISI). While dynamic element matching (DEM) can be applied to convert a portion of the ISI to uncorrelated noise instead of nonlinear distortion, DEM alone fails to prevent ISI from at least introducing strong second-order nonlinear distortion. This paper addresses this problem by proposing, analyzing, and experimentally demonstrating a low-cost add-on technique, called ISI scrambling, that, in conjunction with DEM, causes a DAC’s ISI to be free of nonlinear distortion. The ISI scrambling technique is demonstrated in a 1-GS/s, 14-bit DEM DAC implemented in 90 nm CMOS technology. The DAC’s measured linearity is in line with the state-of-the-art and its measured output power spectra closely match those predicted by this paper’s theoretical results.