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

Magnetic field sensor comprising a first planar thin-film element having a crystalline magnetoresistive material exhibiting resistivity anisotropy in the plane of said first planar thin-film element, having a first and a second easy axis of magnetizations, said first planar thin-film element having,

• a first pair of electrical connections allowing a first electrical measurement current to flow through the first planar thin-film element in a first direction, and
• a second pair of electrical connections allowing a first voltage to be measured in a second direction transverse to the first direction such that the first and second easy axes of magnetizations have comparable magnetization values;
• and
• a first electrical conductor parallel to the first easy axis of magnetization, insulated from the magnetoresistive material, and configured to allow a first electrical control current to flow,
• wherein said first electrical control current induces, in the first planar thin-film element, a first magnetic field which imposes, when the magnetic field sensor is not in use, an orientation of a direction of magnetization of the first planar thin-film element parallel to the second easy axis of magnetization.