Magnetic field sensor system for vehicle speed measurement - has magnetic field sensor with several strip shaped connection leads running parallel in plane extending also outside casing also circuit for operating sensor

摘要

The circuit (2) for operating the magnetic field sensor (1) designed as an IC is mechanically and electrically connected with the connection leads, which also carry the magnetic field sensor, and is surrounded by a casing (20) separated from the casing (10) of the magnetic field sensor. A permanent magnet (4) produces a magnetic initial holding field, which makes surface contact with a surface (11) of the casing (10) of the sensor (1). The distance between the two casings (10,20) is so selected, that the surfaces (41,42) of the permanent magnet make surface contact with the surfaces (11,21) of the casing (10) of the magnetic field sensor and the casing (20) of the IC (2). ADVANTAGE - Spatially small and free from thermal coupling disturbance between sensor and IC for operating sensor.