{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T10:43:41Z","timestamp":1761648221498,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2014,8,27]],"date-time":"2014-08-27T00:00:00Z","timestamp":1409097600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a new micropower analog lock-in amplifier (LIA) suitable for battery-operated applications thanks to its reduced size and power consumption as well as its operation with single-supply voltage. The proposed LIA was designed in a 0.18 \u00b5m CMOS process with a single supply voltage of 1.8 V. Experimental results show a variable DC gain ranging from 24.7 to 42 dB, power consumption of 417 \u00b5W and integration area of 0.013 mm2. The LIA performance was demonstrated by measuring carbon monoxide concentrations as low as 1 ppm in dry N2. The experimental results show that the response to CO of the sensing system can be considerably improved by means of the proposed LIA.<\/jats:p>","DOI":"10.3390\/s140915880","type":"journal-article","created":{"date-parts":[[2014,8,27]],"date-time":"2014-08-27T09:52:39Z","timestamp":1409133159000},"page":"15880-15899","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["An Integrated Low-Power Lock-In Amplifier and Its Application to Gas Detection"],"prefix":"10.3390","volume":"14","author":[{"given":"Paulina","family":"Maya-Hern\u00e1ndez","sequence":"first","affiliation":[{"name":"Electronics Department, Instituto Nacional de Astrof\u00edsica, \u00d3ptica y Electr\u00f3nica (INAOE),  Luis Enrique Erro #1, Tonantzintla 72840, Puebla, Mexico"}]},{"given":"Luis","family":"\u00c1lvarez-Sim\u00f3n","sequence":"additional","affiliation":[{"name":"Electronics Department, Instituto Nacional de Astrof\u00edsica, \u00d3ptica y Electr\u00f3nica (INAOE),  Luis Enrique Erro #1, Tonantzintla 72840, Puebla, Mexico"}]},{"given":"Mar\u00eda","family":"Sanz-Pascual","sequence":"additional","affiliation":[{"name":"Electronics Department, Instituto Nacional de Astrof\u00edsica, \u00d3ptica y Electr\u00f3nica (INAOE),  Luis Enrique Erro #1, Tonantzintla 72840, Puebla, Mexico"}]},{"given":"Bel\u00e9n","family":"Calvo-L\u00f3pez","sequence":"additional","affiliation":[{"name":"Group of Electronic Design, Aragon Institute for Engineering Research, I3A, Facultad de Ciencias, Pedro Cerbuna 12, Zaragoza 50009, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2014,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8173","DOI":"10.3390\/s100908173","article-title":"Micro Cantilever Movement Detection with an Amorphous Silicon Array of Position Sensitive Detectors","volume":"10","author":"Contreras","year":"2010","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"4119","DOI":"10.3390\/s90604119","article-title":"A Portable and Autonomous Magnetic Detection Platform for Biosensing","volume":"9","author":"Germano","year":"2009","journal-title":"Sensors"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"7079","DOI":"10.3390\/s130607079","article-title":"A Novel Solid State Non-Dispersive Infrared CO2 Gas Sensor Compatible with Wireless and Portable Deployment","volume":"13","author":"Gibson","year":"2013","journal-title":"Sensors"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1679","DOI":"10.3390\/s6111679","article-title":"A portable Sensing System for Electronic Tongue Operations","volume":"6","author":"Twomey","year":"2006","journal-title":"Sensors"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Wilmshurst, T.H. 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