A Time-Based Electronic Front-End for a Capacitive Particle Matter Detector

Sensors

Umberto Ferlito¹  AlfioDario Grasso¹  Michele Vaiana²  Giuseppe Bruno² 

[1] Dipartimento di Ingegneria Elettrica Elettronica e Informatica (DIEEI), University of Catania, 95125 Catania, Italy;STMicroelectronics, 95121 Catania, Italy;

关键词: capacitive sensor;    particulate matter (PM);    ring oscillators;    smart sensors;   

DOI  :  10.3390/s21051840

来源: DOAJ

【 摘 要 】

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 3σ resolution equal to 165 aF.

【 授权许可】

Unknown