Patent ID: 7859069

Claim:
An apparatus comprising: a first reference layer having a first magnetization with a first magnetization direction; a second reference layer having a second magnetization with a second magnetization direction substantially perpendicular to the first magnetization direction; a storage layer disposed between the first reference layer and second reference layer, the storage layer comprising either a first data state or a second data state, the first data state comprising a third magnetization about 45° from the first magnetization direction and about 135° from the second magnetization direction and the second data state comprising a fourth magnetization direction opposite the third magnetization direction; the first reference layer, the second reference layer and the storage layer being configured to receive current in a first direction to maintain the first data state and in a second direction opposite the first direction to maintain the second data state; and a circuit which detects whether the storage layer is in the first or second data state during a read operation and further provides current through the storage layer to write the storage layer back to the first or second data state immediately prior to the read operation in response to detecting that the memory cell was changed to the first or second data state by the read operation.