Patent ID: 7414393
Filing Date: 2008-08-19
Classification: B82Y,G01R,H04M

Abstract:
1. A magnetic detection device comprising: a first series circuit, a second series circuit, and a third series circuit, wherein at least one of a plurality of resistance elements forming the first series circuit includes a first magneto-resistance element using a magneto-resistance effect, of which an electric resistance varies with an external magnetic field of any one direction; wherein at least one of a plurality of resistance elements forming the second series circuit includes a second magneto-resistance element using a magneto-resistance effect, of which an electric resistance varies with an external magnetic field of a direction opposite to the one direction; wherein a plurality of resistance elements forming the third series circuit is common resistance elements connected to the resistance elements of the first series circuit and the resistance elements of the second series circuit in a bridge manner; wherein a first output extracting portion of the first series circuit and a second output extracting portion of the second series circuit are individually connected to a common differential output portion through a first switch portion and a third output extracting portion of the third series circuit is connected to the common differential output portion, and wherein a first bridge circuit so as to detect the external magnetic field of the one direction including the first series circuit and the third series circuit connected in parallel to each other is switched to a connection state with the differential output portion when the first output extracting portion is connected to the differential output portion by the first switch portion, and a second bridge circuit so as to detect the external magnetic field of the opposite direction including the second series circuit and the third series circuit connected in parallel to each other is switched to a connection state with the differential output portion when the second output extracting portion is connected to the differential output portion by the first switch portion.