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Author Grassi, M. ♦ Lombardi, A. ♦ Ferragina, V. ♦ Malcovati, P. ♦ Capone, S. ♦ Francioso, L. ♦ Siciliano, P. ♦ Baschirotto, A.
Source IEEE Xplore Digital Library
Content type Text
Publisher Institute of Electrical and Electronics Engineers, Inc. (IEEE)
File Format PDF
Copyright Year ©2006
Language English
Subject Domain (in DDC) Technology ♦ Engineering & allied operations ♦ Applied physics
Subject Keyword Calibration ♦ Frequency measurement ♦ Electrical resistance measurement ♦ Circuit testing ♦ Gas detectors ♦ Integrated circuit measurements ♦ Voltage-controlled oscillators ♦ Linearity ♦ Digital control ♦ Control systems
Abstract In this paper we present a low-cost CMOS wide-dynamic-range integrated interface circuit for indoor resistive gas sensors based on an enhanced oscillator approach. The state of the art of this measurement method has been improved biasing the sensor with a constant voltage, thus increasing linearity by separating the oscillator circuit from the sensing device. Another important novelty of this circuit is an embedded digital measurement control system that extracts the sensor resistance value by the ratio of a reference counter and a resistance dependent one, actually doubling the measurement range in terms of decades. Test results on a silicon prototype show that the proposed circuit achieves, without calibration, a precision of about 0.4% over a range of 4 decades and better than 0.8% over 5 decades (dynamic range: DR>140dB). After calibration, it reaches a precision of 0.8% over a range of 6 decades (DR>165dB). The circuit may also work over a reduced range of 2-3 decades with a throughput up to 100Hz and a precision of 0.2%. Chemical measurements demonstrate the real effectiveness of this system.
Description Author affiliation: Univ. of Pavia, Pavia (Grassi, M.; Lombardi, A.; Ferragina, V.; Malcovati, P.)
ISBN 1424403758
ISSN 19300395
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research ♦ Reading
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2006-10-22
Publisher Place South Korea
Rights Holder Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Size (in Bytes) 4.97 MB
Page Count 4
Starting Page 220
Ending Page 223

Source: IEEE Xplore Digital Library