Patent ID: 7884601
Filing Date: 2011-02-08
Classification: G01R,G06F,H01L

Abstract:
1. A magnetic detection device comprising: a magnetoresistance effect element having a multilayer structure and utilizing a magnetoresistive effect in which an electric resistance of the magnetoresistance effect element changes with respect to an external magnetic field; an integrated circuit connected to the magnetoresistance effect element and outputting a magnetic-field detection signal on the basis of a change in the electric resistance; and a magnet for generating the external magnetic field, wherein the magnetoresistance effect element and the magnet are disposed facing each other with a certain distance therebetween, and wherein at least one of the magnetoresistance effect element and the magnet is supported in a reciprocable fashion towards a front side or rear side of the other one of the magnetoresistance effect element and the magnet or in a rotatable fashion with respect to said other one so as to allow an external magnetic field in a positive direction and an external magnetic field in a negative direction opposite to the positive direction to enter the magnetoresistance effect element from the magnet at different timings in a planar direction parallel to a multilayer interface of the multilayer structure, and wherein, in response to reciprocation or rotation of said at least one of the magnetoresistance effect element and the magnet, the integrated circuit outputs a positive-magnetic-field detection signal on the basis of a change in the electric resistance of the magnetoresistance effect element caused by the external magnetic field in the positive direction, and outputs a negative-magnetic-field detection signal on the basis of a change in the electric resistance of the magnetoresistance effect element caused by the external magnetic field in the negative direction.