Performances and Potentialities of a very simple self-compensated pressure sensor demonstrator

Philippe Menini (1) , G. Blasquez (1) , Patrick Pons (1) , X. Chauffleur (1) , Philippe Dondon (2) , Christian Zardini (3)

1 LAAS - Laboratoire d'analyse et d'architecture des systèmes
2 UB - Université de Bordeaux
3 IXL - Laboratoire d'études de l'intégration des composants et systèmes électroniques

A pressure sensor demonstrator has been designed and mounted using a simple analog digital BICMOS converter and a capacitive Silicon Pyrex sensing cell. The measurements as function of pressure and temperature have enabeled to evaluate the efficiency of a ratiometric scheme to self compensate thermal drifts and non linearities. The best demonstrator is characterized by a thermal coefficent of offset smaller than 20ppm/K and a non linearity lower than or equal to +/81.2% FS. The essential features of the sensor have been modeled by a simple analytical expression. The model specifies the potential gains in pressure sensitivity and non linearity. The best design is based on a quasi symetrical architecture in which stray capacitors are minimized. This study demonstrates the feasibility of self compensated capacitive sensors characterized by overall accuracy in order of a few percents of measuremetns scale over a temperature range of 100K at very lowt cost.

Mots clés: Capacitance measurement; capacitance transducers; circuit modelling; compensation; non linearities; pressure measurmeent; thermal factors; sensors

Domaines: Electronique

Philippe Menini, G. Blasquez, Patrick Pons, X. Chauffleur, Philippe Dondon, et al.. Performances and Potentialities of a very simple self-compensated pressure sensor demonstrator. IEEE Transactions on Instrumentation and Measurement, 1999, VOL 48 (6), pp 1125-1130. ⟨hal-00348524⟩