Nonvolatile semiconductor storage device equipped with a comparison buffer for reducing power consumption during write

Abstract

A semiconductor storage device includes plural bit lines and plural word lines. The memory cell array has plural memory cells that are connected with the bit lines and word lines, and can store data. Plural sense amplifiers detect the data stored in the memory cells. Plural write drivers write data in the memory cells. A comparison buffer temporarily stores the write data to be written in the memory cells by the write driver. In a series of write sequences, the comparison buffer stores the read data from the memory cells selected as the write object and the write data to be written in the selected memory cells. After a series of write sequences, when the pre-charge command for resetting the voltage of the bit lines is received, the write execution command is executed so that the comparison buffer executes write in the selected memory cells.