A capacitance meter based on an oversampling sigma-delta modulator and its application to capacitive sensor interface

Author

Gallorini, R. ; Abouchi, N.

Author_Institution

Lab. Image Signal et Acoustique, Ecoles Superieure de Chimie Phys. Electronique de Lyon, Villeurbanne, France

Volume

3

fYear

2001

fDate

6/23/1905 12:00:00 AM

Firstpage

1537

Abstract

A precision capacitance meter has been developed based on a switched-capacitor sigma delta analog-to-digital converter (ADC). It consists on a second order sigma delta architecture in which the capacitance to be measured takes part of the first integrator. A voltage reference is converted through the sigma delta ADC depending on the capacitance value. The whole operation is insensitive to stray capacitance and amplifier offset. For accurate requirements, calibration as well as temperature compensation have been integrated in the final chip

Keywords

CMOS integrated circuits; calibration; capacitance measurement; capacitive sensors; compensation; integrating circuits; meters; sigma-delta modulation; switched capacitor networks; CMOS technology; SC sigma-delta ADC; analog-to-digital converter; calibration; capacitive sensor interface; integrator; oversampling sigma-delta modulator; precision capacitance meter; second order sigma delta architecture; switched-capacitor ADC; temperature compensation; voltage reference; Capacitance; Capacitive sensors; Circuit noise; Delta modulation; Delta-sigma modulation; Pulse width modulation; Signal to noise ratio; Switches; Transducers; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics, Circuits and Systems, 2001. ICECS 2001. The 8th IEEE International Conference on

Print_ISBN

0-7803-7057-0

Type

conf

DOI

10.1109/ICECS.2001.957508

Filename

957508