Planar thin-film magnetic field sensor for determining directional magnetic fields

• Main Authors: MONTAIGNE FRANCOIS, VAN DAU FRéDéRIC NGUYEN, SCHUHL ALAIN
• Format: Patent
• Language: English
• Published: 20.02.2001
• Edition: 7
• Subjects: ELECTRICITY; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

A magnetic field sensor which includes a planar thin-film element made of a crystalline magnetoresistive material exhibiting resistivity anisotropy in a plane, having a first and a second easy axis of magnetization. The planar thin-film element has electrical connections allowing a first electrical measurement current to flow through the planar thin-film element in a first direction, as well as two other electrical connections allowing a voltage to be measured in a second direction transverse to the first direction. The two easy axes of magnetization have comparable magnetization values. The sensor includes an electrical conductor placed parallel to the first easy axis of magnetization, insulated from the magnetoresistive material, and allowing an electrical control current to flow, in which the control current induces, in the planar thin-film element, a magnetic field which imposes, when the sensor is not in use, an orientation of the direction of magnetization of the element parallel to the second easy axis of magnetization.