A tracking converter for resistive sensors based on a feedback active bridge

Author

Dumas, Norbert ; Hacine, Souha ; Mailly, Frédérick ; Latorre, Laurent ; Nouet, Pascal

Author_Institution

LIRMM, Univ. Montpellier 2, Montpellier, France

fYear

2011

fDate

26-29 June 2011

Firstpage

458

Lastpage

461

Abstract

A so-called active bridge structure has been previously introduced as an alternative to the classical Wheatstone bridge structure combined with a low noise amplifier. It shows an advantage in terms of trade off between SNR and power consumption. The aim of this paper is to show the possibility of using the active bridge in a feedback structure that converts a relative variation of resistance into a digital word. This structure has been applied to a resistive spin-valve sensor with a nominal resistance of 750 Ω. The total power consumption is about 2 mA instead of 4.4 mA that would be consumed only by a Wheatstone bridge. A resolution of 12 bits is expected.

Keywords

circuit feedback; convertors; electric sensing devices; spin valves; active bridge structure; feedback active bridge; resistive sensors; resistive spin-valve sensor; total power consumption; tracking converter; word length 12 bit; Approximation methods; Bridge circuits; Bridges; Low pass filters; Resistance; Sensors; Transistors;

fLanguage

English

Publisher

ieee

Conference_Titel

New Circuits and Systems Conference (NEWCAS), 2011 IEEE 9th International

Conference_Location

Bordeaux

Print_ISBN

978-1-61284-135-9

Type

conf

DOI

10.1109/NEWCAS.2011.5981269

Filename

5981269