Magnetoresistive sensor for determining an angle or a position

US7847542B2 · kind B2 · utility

Assignee

• MEAS Deutschland GmbH · DE

Inventors

• Axel Bartos · Waltrop, DE
• Armin Meisenberg · Dortmund, DE
• Fritz Dettmann · Solms, DE

Key dates

• Filing date: Feb 24, 2004
• Grant date: Dec 7, 2010
• Expiry date: Oct 27, 2026

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/145
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Magnetoresistive sensors which use the AMR or the GMR effect and indicate the direction of the homogeneous magnetic field of a rotatable permanent magnet in the angle measurement or the position of the sensor with respect to a scale, which is magnetized periodically in an alternating direction, for the position measurement, and in which the angle or position value is obtained from the quotient of the output signals from two bridges or half bridges with the aid of arctan interpolation, allow small measurement errors if the output signals have small harmonic components and hysteresis areas. In arrangements according to the invention, this is achieved by the resistors being composed of strips and by continuously varying the resistance-determining angle along the strip longitudinal extent for each constant magnetic field acting on the strips. The resistance-determining angle is between the current and magnetization direction for AMR sensors and is between the magnetization directions of two layer components for GMR sensors.