{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T00:17:29Z","timestamp":1760228249261,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,5,9]],"date-time":"2022-05-09T00:00:00Z","timestamp":1652054400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2021R1A2B5B01001475","2020M3H2A1076786"],"award-info":[{"award-number":["2021R1A2B5B01001475","2020M3H2A1076786"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Science and ICT","award":["2021R1A2B5B01001475","2020M3H2A1076786"],"award-info":[{"award-number":["2021R1A2B5B01001475","2020M3H2A1076786"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a 12-b successive approximation register (SAR) analog-to-digital converter (ADC) for biopotential sensing applications. To reduce the digital-to-analog converter (DAC) switching energy of the high-resolution ADC, we combine merged-capacitor-switching (MCS) and detect-and-skip (DAS) methods, successfully embedded in the subranging structure. The proposed method saves 96.7% of switching energy compared to the conventional method. Without an extra burden on the realization of the calibration circuit, we achieve mismatch calibration by reusing the on-chip DAC. The mismatch data are processed in the digital domain to compensate for the nonlinearity caused by the DAC mismatch. The ADC is realized using a 0.18 \u03bcm CMOS process with a core area of 0.7 mm2. At the sampling rate fS = 9 kS\/s, the ADC achieves a signal-to-noise ratio and distortion (SINAD) of 67.4 dB. The proposed calibration technique improves the spurious-free dynamic range (SFDR) by 7.2 dB, resulting in 73.5 dB. At an increased fS = 200 kS\/s, the ADC achieves a SINAD of 65.9 dB and an SFDR of 68.8 dB with a figure-of-merit (FoM) of 13.2 fJ\/conversion-step.<\/jats:p>","DOI":"10.3390\/s22093600","type":"journal-article","created":{"date-parts":[[2022,5,10]],"date-time":"2022-05-10T00:30:28Z","timestamp":1652142628000},"page":"3600","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A 12-b Subranging SAR ADC Using Detect-and-Skip Switching and Mismatch Calibration for Biopotential Sensing Applications"],"prefix":"10.3390","volume":"22","author":[{"given":"Cong Luong","family":"Nguyen","sequence":"first","affiliation":[{"name":"Information and Communication System-on-Chip (SoC) Research Center, School of Electronics and Information, Kyung Hee University, Yongin 17104, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huu Nhan","family":"Phan","sequence":"additional","affiliation":[{"name":"Information and Communication System-on-Chip (SoC) Research Center, School of Electronics and Information, Kyung Hee University, Yongin 17104, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9160-2183","authenticated-orcid":false,"given":"Jong-Wook","family":"Lee","sequence":"additional","affiliation":[{"name":"Information and Communication System-on-Chip (SoC) Research Center, School of Electronics and Information, Kyung Hee University, Yongin 17104, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1736","DOI":"10.1109\/TCSI.2011.2107214","article-title":"Analysis of power consumption and linearity in capacitive digital-to-analog converters used in successive approximation ADCs","volume":"58","author":"Saberi","year":"2011","journal-title":"IEEE Trans. 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