| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable high speed write-in of a multi-level threshold value in a memory cell. <P>SOLUTION: A threshold value is set to a threshold value distribution range of either of an upper part region or a lower part region in accordance with a threshold value corresponding to write-in data, and it is set to the threshold distribution range of either of the narrower upper part region or the lower part region in the next step, afterward, the same step is repeated, the threshold value corresponding to the write-in data is set at high speed. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
