MEMS high resolution 4-20 mA current sensor for industrial I/O applications

Author

DeNatale, J. ; Borwick, R. ; Stupar, P. ; Anderson, R. ; Garrett, K. ; Morris, W. ; Yao, J.J.

Author_Institution

Rockwell Sci. Co., Thousand Oaks, CA, USA

Volume

2

fYear

2003

Firstpage

1598

Abstract

An isolated MEMS-based 4-20 mA current sensor device has been developed for industrial automation applications. This device consists of a current carrying suspension that is electrically isolated, yet mechanically coupled to a bank of capacitive comb fingers. Under the presence of a magnetic field, the sense current produces a Lorentz force that laterally deflects the device. The deflection is capacitively detected. Using various flexure designs to tune the sensitivity and current capacity, this device can be made highly linear with a sensitivity of 0.25 /spl mu/A.

Keywords

automation; capacitive sensors; electric sensing devices; microsensors; 4 to 20 mA; Lorentz force; MEMS; capacitive comb finger; capacitive detection; current carrying suspension; electrical isolation; flexure design; industrial automation application; magnetic field; sensitivity; Capacitance; Capacitors; Conductors; Etching; Isolation technology; Lorentz covariance; Magnetic fields; Magnetic sensors; Micromechanical devices; Temperature sensors;

fLanguage

English

Publisher

ieee

Conference_Titel

TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003

Conference_Location

Boston, MA, USA

Print_ISBN

0-7803-7731-1

Type

conf

DOI

10.1109/SENSOR.2003.1217086

Filename

1217086