Patent ID: 7523664

Claim:
An acceleration sensor including a housing member, first and second magnetic field generation members with weights, a spring member with a fulcrum attached to said housing member, for supporting said first and second magnetic field generation members with weights and for displacing said first and second magnetic field generation members with weights when an external force with components in first and second axis directions that are perpendicular to each other is applied, and first and second magnetic field detection sensors attached to said housing member to face said first and second magnetic field generation members with weights, respectively, each of said first and second magnetic field detection sensors having two pairs of multi-layered magnetoresistive effect elements each including a magnetization fixed layer and a magnetization free layer, said magnetization fixed layer being magnetically fixed along said first axis direction, one pair of said multi-layered magnetoresistive effect elements in said first magnetic field detection sensor and one pair of said multi-layered magnetoresistive effect elements in said second magnetic field detection sensor being connected in full-bridge configuration, and the other pair of said multi-layered magnetoresistive effect elements in said first magnetic field detection sensor and the other pair of said multi-layered magnetoresistive effect elements in said second magnetic field detection sensor being connected in full-bridge configuration.