An analytical method to determine the response of a micro capacitive pressure sensor

Ashwin Simha, S. M. Kulkarni, S. Meenatchisundaram

Research output: Contribution to specialist publicationArticle

Abstract

The response of a capacitive pressure sensor is generally represented by a fourth order partial differential equation which is complex to solve and does not possess an exact solution. Several attempts have been made earlier through various techniques such as the Galerkin method, Finite Difference Method etc. In this paper an attempt has been made to develop a simple approximate analytical approach to determine the response of a capacitive pressure sensor whose diaphragm is designed to undergo very small deflections (typically less than 25 % of the thickness). The nonuniform gap between the electrodes is mathematically expressed as a combination of the initial gap between the electrodes (in the undeformed state) and a displacement function in (x, y). The proposed displacement function is then utilized in evaluating the capacitance as a function of the applied pressure. The results obtained from the analytical approach are benchmarked against those obtained from COMSOL Multiphysics®, a popular Finite Element Analysis tool in the MEMS industry. It is observed that the results obtained from COMSOL Multiphysics® and those from the analytical approach are in good agreement with a maximum deviation of about 3.38 %.

Original languageEnglish
Pages118-126
Number of pages9
Volume130
No.7
Specialist publicationSensors and Transducers
Publication statusPublished - 01-07-2011

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Capacitive sensors
Pressure sensors
Electrodes
Galerkin methods
Diaphragms
Finite difference method
Partial differential equations
MEMS
Capacitance
Finite element method
Industry

All Science Journal Classification (ASJC) codes

  • Control and Systems Engineering
  • Electrical and Electronic Engineering

Cite this

Simha, A., Kulkarni, S. M., & Meenatchisundaram, S. (2011). An analytical method to determine the response of a micro capacitive pressure sensor. Sensors and Transducers, 130(7), 118-126.
Simha, Ashwin ; Kulkarni, S. M. ; Meenatchisundaram, S. / An analytical method to determine the response of a micro capacitive pressure sensor. In: Sensors and Transducers. 2011 ; Vol. 130, No. 7. pp. 118-126.
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Simha, A, Kulkarni, SM & Meenatchisundaram, S 2011, 'An analytical method to determine the response of a micro capacitive pressure sensor' Sensors and Transducers, vol. 130, no. 7, pp. 118-126.

An analytical method to determine the response of a micro capacitive pressure sensor. / Simha, Ashwin; Kulkarni, S. M.; Meenatchisundaram, S.

In: Sensors and Transducers, Vol. 130, No. 7, 01.07.2011, p. 118-126.

Research output: Contribution to specialist publicationArticle

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Simha A, Kulkarni SM, Meenatchisundaram S. An analytical method to determine the response of a micro capacitive pressure sensor. Sensors and Transducers. 2011 Jul 1;130(7):118-126.