Arrangement for detecting the zero crossing of a magnetic field

摘要

The arrangement consists of a current source (13), a thin film coil (6), a magnetoresistive magnetic film (2) and an evaluating circuit (14). The thinfilm coil (6) is connected to the current source (13) in series with the magnetic film (2). The turns of the thinfilm coil (6) extend in an area aligned with the magnetic film (2) and parallel with the longitudinal direction of the latter. In the magnetic film (2) a static auxiliary field is generated in the direction of its heavy magnetisation axis, which field shifts the operating point into the area of rotating remagnetisation. At the zero crossing of an alternating magnetic field applied to the magnetic film (2) in the magnetic direction of preference, the magnetic film (2) abruptly changes its electrical resistance. <IMAGE>