US Patent 7499372 Semiconductor memory device

When writing 16-bit write data to the memory array 100 which can store data of 8 bits per 1 row, the semiconductor memory device 10 first writes the upper 8 bits to the 1st write restricted row of the memory array 100. The increment controller 150 determines whether or not the value of the existing data written to the memory array 100 and the write data used for writing latched to the 8-bit latch register 170 match. When the existing data and the write data match, the increment controller 150 outputs the write enable signal WEN1 to the write/read controller 140 and executes the writing of the lower 8 bits of write data to the memory array 100.