Patent ID: 8278916
Filing Date: 2012-10-02
Classification: G01D

Abstract:
1. A rotational angle sensor, comprising: a magnet rotor in which multiple magnetic poles are formed along a circumferential direction of the magnet rotor; and three sensor devices that output sensor signals based on a change in magnetic flux caused by rotation of the magnet rotor, wherein the three sensor devices are arranged on a circle concentric with the magnet rotor at regular angle intervals, and wherein each of the sensor devices includes three bridge circuits each of which has a pair of spin valve magnetic resistances that are connected in series in such a manner that magnetization directions of spin fixed layers of the spin valve magnetic resistances are opposite to each other, and each of the sensor devices is formed in such a manner that phases of the sensor signals output from the respective bridge circuits are offset from each other by an electrical angle of 120°.