Magnetic field sensor and instrument comprising such a sensor
US5686837A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 17, 1995 |
| Grant date | Nov 11, 1997 |
| Priority date | — |
| Expiry date | Apr 17, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/09
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic field sensor is composed of layered magnetoresistive elements which are arranged in a bridge on a substrate. The magnetoresistive elements comprise two ferromagnetic layers which exhibit an uni-axial anisotropy in one plane and are separated by a non-ferromagnetic layer. During the manufacture of the sensor the magnetization directions of these ferromagnetic layers are laid down so that two elements in two adjacent branches of the bridge exhibit an opposed sensitivity to external magnetic fields. Moreover, in each magnetoresistive element the magnetization of a ferromagnetic layer is adjusted substantially perpendicularly to the magnetization direction of the other ferromagnetic layer. As a result auxiliary fields are no longer required for the measurement of small magnetic fields and the sensor is substantially free of hysteresis and has an enhanced linearity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.