Low Noise CMOS Amplifier for a Piezoresistive Magnetic Field Sensor - LIRMM - Laboratoire d’Informatique, de Robotique et de Microélectronique de Montpellier Access content directly
Conference Papers Year : 2003

Low Noise CMOS Amplifier for a Piezoresistive Magnetic Field Sensor

Abstract

A two-axis MEMS magnetometer with integrated signal processing has been developed for a micro-compass application. The fabrication process is fully industrial and relies on bulk wet etching of CMOS dies. This technology offers cost- effective batch fabrication. Earth magnetic field measurement is achieved using piezoresistive gauges on a cantilever beam actuated by means of the Lorentz force. Due to low signal level available across the gauges, on-chip amplification with very high gain and low noise is then required. A fully differential amplifier based on a differential pair is suitable for this application. Circuit design approach is discussed in this paper. The obtained performances in terms of noise are compared to an instrumentation amplifier. Finally, a sensing resolution of 0.9 μT is demonstrated with such a differential amplifier instead of 2.1 μT resulting from standard-cell based instrumentation amplifier.
Fichier principal
Vignette du fichier
D158.PDF (351.92 Ko) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

lirmm-00269472 , version 1 (03-04-2008)

Identifiers

  • HAL Id : lirmm-00269472 , version 1

Cite

Norbert Dumas, Laurent Latorre, Pascal Nouet. Low Noise CMOS Amplifier for a Piezoresistive Magnetic Field Sensor. DCIS: Design of Circuits and Integrated Systems, Nov 2003, Ciudad Real, Spain. pp.639-644. ⟨lirmm-00269472⟩
127 View
526 Download

Share

Gmail Facebook X LinkedIn More