Patent ID: 6694822
Filing Date: 2004-02-24
Classification: B82Y,G01L

Abstract:
A method of sensing pressure in which applied pressure causes a change in magnetization vectors of ferromagnetic layers and a corresponding change in resistance comprising the steps of:providing a sensing device with a sensor including a plurality of layers, the plurality of layers comprising a non magnetic conducting layer disposed between at least two ferromagnetic layers, at least one of the ferromagnetic layers having a non-zero magnetostriction; biasing at least one of the two ferromagnetic layers with an externally supplied current such that the magnetization vectors of each ferromagnetic layer in a biased state are changed from an initial state; and sensing a resistance in the plurality of layers upon application of pressure while the externally supplied current is being applied, the applied pressure causing the magnetization vectors of at least one of the ferromagnetic layers to change from the biased state, and thereby result in a change in resistance.