By Topic

Signal Conditioning System With a 4–20 mA Output for a Resonant Magnetic Field Sensor Based on MEMS Technology

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
Dominguez-Nicolas, S.M. ; Centro de Investig. en Micro y Nanotecnologia, Univ. Veracruzana, Boca del Río, Mexico ; Juarez-Aguirre, R. ; Garcia-Ramirez, P.J. ; Herrera-May, A.L.

Several resonant magnetic field sensors based on microelectromechanical systems (MEMS) technology use piezoresistive detection techniques to convert the magnetic field signal into an electrical signal. We present a signal conditioning system implemented in a printed circuit board (PCB) for a resonant magnetic field sensor based on MEMS technology. This sensor is formed by a resonant structure of thin silicon beams (5 μm thick), an aluminum loop (1 μm thick), and a Wheatstone bridge with four p-type piezoresistors. The Wheatstone bridge is biased with an alternating voltage of 2 Vpp at 1 kHz and the aluminum loop is supplied using an alternating current with a root-mean-square (RMS) value of 20 mA. This current is applied to the resonant frequency of the sensor (14.38 kHz) through an oscillator that has a frequency stability of ± 100 ppm at atmospheric temperature and a resolution of 1 Hz. The proposed system obtains the sensor's electrical response in voltage or current mode, which presents an approximately linear behavior for a range of magnetic field density from -150 to +150 μT. This system minimizes the offset of the sensor's electrical response and allows the detection of the polarity and magnitude of the magnetic field density. A virtual instrument is designed using Lab VIEW software to visualize the 4-20 mA output of the sensor. The designed system can help the development of portable measurement equipment to detect (at pressure atmospheric) low magnetic field densities with a sensitivity and resolution of 4 V · T-1 and 1 μT, respectively.

Published in:

Sensors Journal, IEEE  (Volume:12 ,  Issue: 5 )