{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T14:43:40Z","timestamp":1785163420845,"version":"3.55.0"},"reference-count":11,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2015,9,30]],"date-time":"2015-09-30T00:00:00Z","timestamp":1443571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A biopotential acquisition analog front-end (AFE) integrated circuit (IC) is presented. The biopotential AFE includes a capacitively coupled chopper instrumentation amplifier (CCIA) to achieve low input referred noise (IRN) and to block unwanted DC potential signals. A DC servo loop (DSL) is designed to minimize the offset voltage in the chopper amplifier and low frequency respiration artifacts. An AC coupled ripple rejection loop (RRL) is employed to reduce ripple due to chopper stabilization. A capacitive impedance boosting loop (CIBL) is designed to enhance the input impedance and common mode rejection ratio (CMRR) without additional power consumption, even under an external electrode mismatch. The AFE IC consists of two-stage CCIA that include three compensation loops (DSL, RRL, and CIBL) at each CCIA stage. The biopotential AFE is fabricated using a 0.18 \u03bcm one polysilicon and six metal layers (1P6M) complementary metal oxide semiconductor (CMOS) process. The core chip size of the AFE without input\/output (I\/O) pads is 10.5 mm2. A fourth-order band-pass filter (BPF) with a pass-band in the band-width from 1 Hz to 100 Hz was integrated to attenuate unwanted signal and noise. The overall gain and band-width are reconfigurable by using programmable capacitors. The IRN is measured to be 0.94 \u03bcVRMS in the pass band. The maximum amplifying gain of the pass-band was measured as 71.9 dB. The CIBL enhances the CMRR from 57.9 dB to 67 dB at 60 Hz under electrode mismatch conditions.<\/jats:p>","DOI":"10.3390\/s151025139","type":"journal-article","created":{"date-parts":[[2015,10,1]],"date-time":"2015-10-01T02:15:03Z","timestamp":1443665703000},"page":"25139-25156","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Fully Integrated Biopotential Acquisition Analog Front-End IC"],"prefix":"10.3390","volume":"15","author":[{"given":"Haryong","family":"Song","sequence":"first","affiliation":[{"name":"Department of Electronics, Chungnam National University, Daejeon, 305-764, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunjong","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Electronics, Chungnam National University, Daejeon, 305-764, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyungseup","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronics, Chungnam National University, Daejeon, 305-764, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5348-3585","authenticated-orcid":false,"given":"Hyoungho","family":"Ko","sequence":"additional","affiliation":[{"name":"Department of Electronics, Chungnam National University, Daejeon, 305-764, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3077","DOI":"10.3390\/s130303077","article-title":"A low-power bio-potential acquisition system with flexible PDMS dry electrodes for portable ubiquitous healthcare applications","volume":"13","author":"Chen","year":"2013","journal-title":"Sensors"},{"key":"ref_2","unstructured":"Tu, C.C., and Lin, T.H. (2014, January 11\u201314). Measurement and parameter characterization of pseudo-resistor based CCIA for biomedical applications. Proceedings of IEEE International symposium on Bioelectronics and Bioinformatics, Taiwan."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1109\/TBCAS.2011.2170985","article-title":"A 160 \u00b5W 8-channel active electrode system for EEG monitoring","volume":"5","author":"Xu","year":"2011","journal-title":"IEEE Trans. Biomed. Circuits Syst."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"552","DOI":"10.1109\/TBCAS.2012.2224113","article-title":"A 160 \u00b5A biopotential acquisition IC with fully integrated IA and motion artifact suppression","volume":"6","author":"Kim","year":"2012","journal-title":"IEEE Trans. Biomed. 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Solid State Circuit"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/10\/25139\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:49:33Z","timestamp":1760215773000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/10\/25139"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,9,30]]},"references-count":11,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2015,10]]}},"alternative-id":["s151025139"],"URL":"https:\/\/doi.org\/10.3390\/s151025139","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,9,30]]}}}