| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem of the difficulty of reducing an erasure voltage which obstructs the realization of single power voltage driving. <P>SOLUTION: The intial value V0 of data is stored in the memory cell group of arbitrary M bits in storage areas B0 to B10 having a capacity of (N+1) multiple, e.g., 11 times larger, of the bit number M necessary for data storage. When a data rewriting is instructed, instead of erasing the initial value V10 and writing a new data value in the same memory cell, the unused other memory cell group of M bits is selected to write a new data value V1. By executing this operation for each data rewriting instruction, the writing of new data values V1 to V10 is executed up to 10 times. When reading, by reading a latest value, data rewriting not using erasure is executed. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
