{"title":"The Error Analysis of Bit Weight Self-Calibration Methods for High-Resolution SAR ADCs","authors":"Yanhang Chen;Siji Huang;Qifeng Huang;Yifei Fan;Jie Yuan","doi":"10.1109/TVLSI.2024.3458071","DOIUrl":null,"url":null,"abstract":"High-resolution successive approximation register (SAR) analog-to-digital converters (ADCs) commonly need to calibrate their bit weights. Due to the nonidealities of the calibration circuits, the calibrated bit weights carry errors. This error could propagate during the calibration procedure. Due to the high precision requirement of these ADCs, such residue error commonly becomes the signal-to-noise-and-distortion ratio (SNDR) bottleneck of the overall ADC. This article presents an analysis of the residue error from bit weight self-calibration methods of high-resolution SAR ADCs. The major sources contributing to this error and the error reduction methods are quantitively analyzed. A statistical analysis of the noise-induced random error is developed. Our statistical model finds that the noise-induced random error follows the chi-square distribution. In practice, this random error is commonly reduced by repetitively measuring and averaging the calibrated bit weights. Our statistical model quantifies this bit weight error and leads to a clearer understanding of the error mechanism and design trade-offs. Following our chi-square model, the SNDR degradation due to the circuit noise during the calibration can be easily estimated without going through the time-consuming traditional transistor-level design and simulation process. The required repetition time can also be calculated. The bit-weight error models derived in this article are verified with measurement on a 16-bit SAR ADC design in a 180-nm CMOS process. Results from our model match both simulations and measurements well.","PeriodicalId":13425,"journal":{"name":"IEEE Transactions on Very Large Scale Integration (VLSI) Systems","volume":"32 11","pages":"1983-1992"},"PeriodicalIF":2.8000,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IEEE Transactions on Very Large Scale Integration (VLSI) Systems","FirstCategoryId":"5","ListUrlMain":"https://ieeexplore.ieee.org/document/10684141/","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"COMPUTER SCIENCE, HARDWARE & ARCHITECTURE","Score":null,"Total":0}
引用次数: 0
Abstract
High-resolution successive approximation register (SAR) analog-to-digital converters (ADCs) commonly need to calibrate their bit weights. Due to the nonidealities of the calibration circuits, the calibrated bit weights carry errors. This error could propagate during the calibration procedure. Due to the high precision requirement of these ADCs, such residue error commonly becomes the signal-to-noise-and-distortion ratio (SNDR) bottleneck of the overall ADC. This article presents an analysis of the residue error from bit weight self-calibration methods of high-resolution SAR ADCs. The major sources contributing to this error and the error reduction methods are quantitively analyzed. A statistical analysis of the noise-induced random error is developed. Our statistical model finds that the noise-induced random error follows the chi-square distribution. In practice, this random error is commonly reduced by repetitively measuring and averaging the calibrated bit weights. Our statistical model quantifies this bit weight error and leads to a clearer understanding of the error mechanism and design trade-offs. Following our chi-square model, the SNDR degradation due to the circuit noise during the calibration can be easily estimated without going through the time-consuming traditional transistor-level design and simulation process. The required repetition time can also be calculated. The bit-weight error models derived in this article are verified with measurement on a 16-bit SAR ADC design in a 180-nm CMOS process. Results from our model match both simulations and measurements well.
期刊介绍:
The IEEE Transactions on VLSI Systems is published as a monthly journal under the co-sponsorship of the IEEE Circuits and Systems Society, the IEEE Computer Society, and the IEEE Solid-State Circuits Society.
Design and realization of microelectronic systems using VLSI/ULSI technologies require close collaboration among scientists and engineers in the fields of systems architecture, logic and circuit design, chips and wafer fabrication, packaging, testing and systems applications. Generation of specifications, design and verification must be performed at all abstraction levels, including the system, register-transfer, logic, circuit, transistor and process levels.
To address this critical area through a common forum, the IEEE Transactions on VLSI Systems have been founded. The editorial board, consisting of international experts, invites original papers which emphasize and merit the novel systems integration aspects of microelectronic systems including interactions among systems design and partitioning, logic and memory design, digital and analog circuit design, layout synthesis, CAD tools, chips and wafer fabrication, testing and packaging, and systems level qualification. Thus, the coverage of these Transactions will focus on VLSI/ULSI microelectronic systems integration.