| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor memory to which data is written at high speed. <P>SOLUTION: The semiconductor memory is provided with a electrically rewritable nonvolatile memory cell, and one memory cell is provided with; a memory cell array in which one of first to fourth data defined as order of threshold voltages is stored; a read/write circuit for reading/writing the data of the memory cell array; and a controller for controlling the read/write circuit and executing the first write sequence of writing second data in a first selected memory cell in the selection page of the memory cell array initialized to first data, and the second write sequence of writing fourth data in the second selected memory cell of the memory cells for storing the second or first data in the selection page, and subsequently writing third data in the third selected memory cell for storing the first or second data in the selection page. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
