The differential magnetoresistive sensor FP 212 D 250-22 consists of two series coupled magneto resistors (D-type InSb/NiSb semiconductor resistors whose value can be magnetically controlled) which are mounted onto an insulated ferrite substrate. The sensor is encapsulated in a plastic package and has three connecting terminals. The basic resistance of the total system is 2x250 . A permanent magnet which supplies a biasing magnetic field is fixed on the base of the sensor. Semiconductor Group