{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T10:22:42Z","timestamp":1781259762115,"version":"3.54.1"},"reference-count":43,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,6]],"date-time":"2021-03-06T00:00:00Z","timestamp":1614988800000},"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>This paper introduces the electronic interface for a capacitive airborne particle matter detector. The proposed circuit relies on two matched ring oscillators and a mixer to detect the frequency difference induced by the deposition of a particle onto an interdigitated capacitor, which constitutes the load of one of the oscillators. The output of the mixer is digitized through a simple counter. In order to compensate the oscillation frequency offset of the two ring oscillators due to process and mismatch variations, a capacitive trimming circuit has been implemented. The sensor is connected to host through an I2C interface for communication and configuration. The sensor has been implemented using a standard 130-nm CMOS technology by STMicroelectronics and occupies 0.12-mm2 die area. Experimental measurements using talcum powder show a sensitivity of 60 kHz\/fF and a 3\u03c3 resolution equal to 165 aF.<\/jats:p>","DOI":"10.3390\/s21051840","type":"journal-article","created":{"date-parts":[[2021,3,7]],"date-time":"2021-03-07T21:52:15Z","timestamp":1615153935000},"page":"1840","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Time-Based Electronic Front-End for a Capacitive Particle Matter Detector"],"prefix":"10.3390","volume":"21","author":[{"given":"Umberto","family":"Ferlito","sequence":"first","affiliation":[{"name":"Dipartimento di Ingegneria Elettrica Elettronica e Informatica (DIEEI), University of Catania, 95125 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5707-9683","authenticated-orcid":false,"given":"Alfio Dario","family":"Grasso","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria Elettrica Elettronica e Informatica (DIEEI), University of Catania, 95125 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michele","family":"Vaiana","sequence":"additional","affiliation":[{"name":"STMicroelectronics, 95121 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Bruno","sequence":"additional","affiliation":[{"name":"STMicroelectronics, 95121 Catania, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/j.sna.2014.09.003","article-title":"Capacitive Detection of Micrometric Airborne Particulate Matter for Solid-State Personal Air Quality Monitors","volume":"219","author":"Carminati","year":"2014","journal-title":"Sens. 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