Patent ID: 7944736

Claim:
A magnetoresistive device comprising at least one pair of magnetoresistive elements comprising first and second magnetoresistive elements, each comprising at least a hard ferromagnetic layer that is trapped in a permanent direction and serves as a reference layer, and a soft ferromagnetic layer separated from the hard ferromagnetic layer by a separator layer, the soft layer being made for each of the first and second magnetoresistive elements in such a manner as to present two stable magnetic states, the device being characterized in that the first and second magnetoresistive elements of a pair of magnetoresistive elements are placed relative to each other in magnetostatic interaction in such a manner that a magnetic flux passing between the first and second elements closes through the soft ferromagnetic layers of the first and second elements, in that a write device is associated with each pair of magnetoresistive elements to control the magnetization of each soft layer, in that a read conductor line is associated with each first and second magnetoresistive element to detect the magnetic state of the soft layer by measuring the value of the corresponding magnetoresistance, in that the soft ferromagnetic layers of the first and second magnetoresistive elements remain oriented so as to be substantially antiparallel relative to each other, whatever their stable state, while the hard ferromagnetic layers of the first and second magnetoresistive elements are oriented substantially in parallel; in that each of the first and second magnetoresistive elements defines a tunnel junction whose component layers pass an electric current flowing perpendicularly to the planes of said layers, and in that each read conductor line comprises a first conductor line segment connected to the bottom of a magnetoresistive element and a second conductor line segment connected to the top of the same magnetoresistive element, these conductor line segments being essentially perpendicular to the planes of the layers constituting the first and second magnetoresistive elements.