Non-volatile semiconductor memory device allowing concurrent data writing and data reading

A non-volatile semiconductor memory device comprising:

• a plurality of non-volatile memory cells, arranged in rows and columns, each having physical state thereof set according to storage information and storing information in a non-volatile manner based on said physical state;
• a write circuit for supplying, in data writing, a write current to a write target memory cell among said plurality of non-volatile memory cells, to perform data writing to said write target memory cell;
• a read circuit for performing data reading from a read target memory cell among said plurality of non-volatile memory cells, said read circuit operable concurrently with said write circuit;
• a plurality of write bit lines, arranged corresponding to memory cell columns, each for supplying a first write current from said write circuit to the memory cells on a corresponding column;
• and
• a plurality of read bit lines, arranged separately from the write bit lines and corresponding to the memory cell columns, for supplying a read current for reading data of the read target memory cell from said read circuit,
• said write circuit performing data writing, after activation of said read circuit, with said read target memory cell being said write target memory cell, concurrently with reading by said read circuit, the reading and writing operations being repeated while supplying the read current to the read bit line of the read target memory cell until data read by said read circuit coincides with write data of said write circuit.