Giant magnetoresistance sensor for ferromagnetic target detector in automobile engine environment, has giant magnetoresistance circuit comprising cells sensitive along axis perpendicular to reference axis of permanent magnet

摘要

The sensor (1) has a permanent magnet (3) with a surface (16) perpendicular to a reference axis (z) of the magnet. A magnetic/ferromagnetic ring (4) is placed on the magnet surface. The ring has constant thickness walls (8) continuously surrounding a cavity (5) traversing the ring along the axis. The cavity is filled with a non-magnetic material. A giant magnetoresistance (GMR) circuit (11) is positioned above the cavity such that the circuit is included in a plane perpendicular to the axis. The circuit has GMR cells (13a-13c) sensitive along an axis perpendicular to the reference axis.