{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T04:16:02Z","timestamp":1768709762106,"version":"3.49.0"},"reference-count":31,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,6,10]],"date-time":"2020-06-10T00:00:00Z","timestamp":1591747200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004281","name":"Narodowe Centrum Nauki","doi-asserted-by":"publisher","award":["2016\/23\/B\/ST7\/03733"],"award-info":[{"award-number":["2016\/23\/B\/ST7\/03733"]}],"id":[{"id":"10.13039\/501100004281","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The paper presents an operational transconductance amplifier (OTA) with low transconductance (0.62\u20136.28 nS) and low power consumption (28\u2013270 nW) for the low-frequency analog front-ends in biomedical sensor interfaces. The proposed OTA implements an innovative, highly linear voltage-to-current converter based on the channel-length-modulation effect, which can be rail-to-rail driven. At 1-V supply and 1-Vpp asymmetrical input driving, the linearity error in the current-voltage characteristics is 1.5%, while the total harmonic distortion (THD) of the output current is 0.8%. For a symmetrical 2-Vpp input drive, the linearity error is 0.3%, whereas THD reaches 0.2%. The linearity is robust for the mismatch and the process-voltage-and-temperature (PVT) variations. The temperature drift of transconductance is 10 pS\/\u00b0C. The prototype circuit was fabricated in 180-nanometer CMOS technology.<\/jats:p>","DOI":"10.3390\/s20113303","type":"journal-article","created":{"date-parts":[[2020,6,15]],"date-time":"2020-06-15T05:56:27Z","timestamp":1592200587000},"page":"3303","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["A 1-nS 1-V Sub-1-\u00b5W Linear CMOS OTA with Rail-to-Rail Input for Hz-Band Sensory Interfaces"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9262-9575","authenticated-orcid":false,"given":"Jacek","family":"Jakusz","sequence":"first","affiliation":[{"name":"Faculty of Electronics, Gda\u0144sk University of Technology, 80-233 Gda\u0144sk, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5476-348X","authenticated-orcid":false,"given":"Waldemar","family":"Jendernalik","sequence":"additional","affiliation":[{"name":"Faculty of Electronics, Gda\u0144sk University of Technology, 80-233 Gda\u0144sk, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0846-2782","authenticated-orcid":false,"given":"Grzegorz","family":"Blakiewicz","sequence":"additional","affiliation":[{"name":"Faculty of Electronics, Gda\u0144sk University of Technology, 80-233 Gda\u0144sk, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2909-5712","authenticated-orcid":false,"given":"Miron","family":"K\u0142osowski","sequence":"additional","affiliation":[{"name":"Faculty of Electronics, Gda\u0144sk University of Technology, 80-233 Gda\u0144sk, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stanis\u0142aw","family":"Szczepa\u0144ski","sequence":"additional","affiliation":[{"name":"Faculty of Electronics, Gda\u0144sk University of Technology, 80-233 Gda\u0144sk, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1067","DOI":"10.1109\/JSSC.2009.2014707","article-title":"A 1-V 450-nW Fully Integrated Programmable Biomedical Sensor Interface Chip","volume":"44","author":"Zou","year":"2009","journal-title":"IEEE J. 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