{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T12:04:21Z","timestamp":1774526661497,"version":"3.50.1"},"reference-count":22,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2014,9,16]],"date-time":"2014-09-16T00:00:00Z","timestamp":1410825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["Project NEUWalk, 258653"],"award-info":[{"award-number":["Project NEUWalk, 258653"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A fully-integrated complementary metal-oxide semiconductor (CMOS) sensor for combined temperature and humidity measurements is presented. The main purpose of the device is to monitor the hermeticity of micro-packages for implanted integrated circuits and to ensure their safe operation by monitoring the operating temperature and humidity on-chip. The smart sensor has two modes of operation, in which either the temperature or humidity is converted into a digital code representing a frequency ratio between two oscillators. This ratio is determined by the ratios of the timing capacitances and bias currents in both oscillators. The reference oscillator is biased by a current whose temperature dependency is complementary to the proportional to absolute temperature (PTAT) current. For the temperature measurement, this results in an exceptional normalized sensitivity of about 0.77%\/\u00b0C at the accepted expense of reduced linearity. The humidity sensor is a capacitor, whose value varies linearly with relative humidity (RH) with a normalized sensitivity of 0.055%\/% RH. For comparison, two versions of the humidity sensor with an area of either 0.2 mm2 or 1.2 mm2 were fabricated in a commercial 0.18 \u03bcm CMOS process. The on-chip readout electronics operate from a 5 V power supply and consume a current of approximately 85 \u00b5A.<\/jats:p>","DOI":"10.3390\/s140917192","type":"journal-article","created":{"date-parts":[[2014,9,16]],"date-time":"2014-09-16T11:38:13Z","timestamp":1410867493000},"page":"17192-17211","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["A CMOS Smart Temperature and Humidity Sensor with Combined Readout"],"prefix":"10.3390","volume":"14","author":[{"given":"Clemens","family":"Eder","sequence":"first","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Virgilio","family":"Valente","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nick","family":"Donaldson","sequence":"additional","affiliation":[{"name":"Department of Medical Physics and Bioengineering, University College London, Malet Place, WC1E 6BT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0623-963X","authenticated-orcid":false,"given":"Andreas","family":"Demosthenous","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1109\/TIA.2013.2243392","article-title":"Experimental study of the optimum operating conditions of a pilot-scale tribo-aero-electrostatic separator for mixed granular solids","volume":"49","author":"Miloudi","year":"2013","journal-title":"IEEE Trans. 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