| 摘要 |
<P>PROBLEM TO BE SOLVED: To avoid excessive erasing/writing of a memory unit and shorten a writing time. <P>SOLUTION: A memory control circuit performs a reading operation for reading a data value stored in a memory unit (MU11), and starts a reverse writing operation for controlling charge amounts of first and second floating gates of the memory unit (MU11) so that a reverse value (XRD1) of the data value read by the reading operation is written into the memory unit (MU11), finishes the reverse writing operation before writing of the reverse value (XRD1) into the memory unit (MU11) is completed, and then performs a normal writing operation for controlling the charge amounts of the first and second floating gates of the memory unit (MU11) so that a writing data value (WD1) to be written into the memory unit (MU11) is written into the memory unit (MU11). <P>COPYRIGHT: (C)2012,JPO&INPIT |
