Magnetic memory device and controlling method thereof

A magnetic memory device, comprising:

• a memory cell array comprising memory cells including magnetic tunnel junction elements, each memory cell electrically connected between a source line and a bit line, the memory cell array including a first region and a second region, the second region being a redundancy region of the memory cell array;
• and
• a control circuit configured to perform a screening test on the first region of memory cell array before writing any data addressed to the first region of the memory cell array, the screening test determining whether an abnormal cell is present first region of the memory cell array, and then to write data to the second region if the abnormal cell is present in the first region.

A writing operation control method of a magnetic memory device, comprising:

• performing a screening test on a memory cell array before writing data to the memory cell array, the memory cell array comprising memory cells including magnetic tunnel junction elements, each memory cell being electrically connected between a source line and a bit line, the screening test determining whether an abnormal cell is present in the memory cell array;
• and
• writing the data to the memory cell array by applying a first voltage to a first memory cell in the memory cell array to write data to the first memory cell if the abnormal cell is not present in the memory cell array, and applying a second voltage to the first memory cell if the abnormal cell is present in the memory cell array, the second voltage being different than the first voltage.