Controlled temperature, thermal-assisted magnetic memory device

A controlled temperature, thermal-assisted magnetic memory device comprising:

• an array of SVM cells, the SVM cells characterized by an alterable orientation of magnetization and comprising a material wherein the coercivity is decreased upon an increase in temperature;
• at least one reference SVM cell substantially similar to the SVM cells of the array, the reference SVM cell positioned within close proximity to the array;
• and
• a feedback controlled temperature controller receiving a reference voltage and receiving a feedback voltage from the reference SVM cell when power is applied to the reference SVM cell and a selected array SVM cell to heat the reference SVM cell and the selected array SVM cell, the feedback controlled temperature controller adjusting the applied power to minimize the difference between the feedback voltage and reference voltage.

A controlled temperature, thermal-assisted magnetic memory device comprising:

• a plurality of parallel electrically conductive rows;
• a plurality of parallel electrically conductive columns crossing the rows, thereby forming a cross-point array with a plurality of intersections;
• a plurality of SVM cells, each SVM cell in electrical contact with and located at an intersection between a row and column, each SVM cell comprising a material wherein the coercivity is decreased upon an increase in temperature;
• at least one reference SVM cell substantially similar to the SVM cells of the cross-point array, the reference SVM cell positioned in close proximity to the cross-point array;
• at least one temperature sensor thermally coupled to each at least one reference SVM cell;
• and
• a feedback controlled temperature controller receiving a reference voltage and receiving a feedback voltage from at least one temperature sensor when power is applied to the sensor coupled reference SVM cell, the feedback controlled temperature controller adjusting the applied power to minimize the difference between the feedback voltage and the reference voltage;
• wherein substantially contemporaneously with the application and adjustment of power to the reference SVM cell, a substantially identical power is applied and adjusted to a selected cross-point array SVM cell.

A method of performing a write operation on a selected SVM cell in a controlled temperature, thermal-assisted magnetic memory device consisting of an array of SVM cells wherein their coercivity is decreased upon an increase in temperature, a reference SVM cell substantially similar to and in close proximity to the array, and a feedback controlled temperature controller having a temperature sensor thermally coupled to the reference SVM cell, the method comprising:

• selecting a specific SVM cell from the array;
• applying a first power to the reference SVM cell, the first power heating the reference SVM cell;
• applying a second power, substantially identical to the first power, to the selected SVM cell, the second power heating selected SVM cell;
• sensing a feedback voltage from the temperature sensor coupled to the reference SVM cell;
• comparing the feedback voltage to a reference voltage;
• adjusting the first power applied to the reference SVM cell to minimize the difference between the feedback voltage and the reference voltage;
• adjusting the second power applied to the selected SVM cell to be substantially identical to the adjusted first voltage;
• and
• applying a magnetic field to the selected SVM cell;
• wherein the orientation of magnetization of the selected array SVM cell may be changed, the magnetic field being greater than the coercivity of the heated selected array SVM cell.

A computer system comprising:

• a main board;
• at least one central processing unit (CPU) coupled to the main board;
• and
• at least one memory store joined to the CPU by the main board, the memory store including;
• an array of SVM cells, the SVM cells characterized by an alterable orientation of magnetization and comprising a material wherein the coercivity is decreased upon an increase in temperature;
• at least one reference SVM cell substantially similar to the SVM cells of the array, the reference SVM cell positioned within close proximity to the array;
• at least one temperature sensor thermally coupled to each at least one reference SVM cell;
• and
• a feedback controlled temperature controller receiving a reference voltage and feedback voltage from at least one temperature sensor when power is applied to the sensor coupled reference SVM cell and a selected array SVM cell to heat the reference SVM cell and a selected array SVM cell, the feedback controlled temperature controller adjusting the applied power to minimize the difference between the feedback voltage and reference voltage.