Magnetoresistive sensor systems with stray field cancellation utilizing auxiliary sensor signals

US10509082B2 · kind B2 · utility

Assignee

• NXP B.V. · NL

Inventors

• Jan Przytarski · Hamburg, DE
• Jörg Kock · Burgwedel, DE
• Stephan Marauska · Kaltenkirchen, DE
• Edwin Schapendonk · Oss, NL

Key dates

• Filing date: Feb 8, 2018
• Grant date: Dec 17, 2019
• Expiry date: Jun 7, 2038

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/098
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A system includes first and second magnetic sense elements for producing first and second output signals, respectively, in response to an external magnetic field along a sensing axis parallel to a plane of the first sense element, a magnetization direction of the second element being rotated in the plane relative to a magnetization direction of the first element. The second output signal differs from the first output signal in dependency to a magnetic interference field along a non-sensing axis of the first magnetic field. A processing circuit, receives the first and second output signals, identifies from a relationship between the first and second output signals an influence of the magnetic interference field on the first output signal, and applies a correction factor to the first output signal to produce a resultant output signal in which the influence of the magnetic interference field is substantially removed.