| 摘要 |
<p>PURPOSE: To verify a programming failured cell and to reprogram only the failured cell. CONSTITUTION: Concerning an over programming preventing method, plural rows 15 of memory cells 10 at a floating gate 13 are erased, one cell selected out of the plural rows 15 at least is programmed during 1st time, and programming is simultaneously executed during the 1st time. In order to discriminate the respective program states of cells 10, the plural rows 15 of the cells 10 are read out, and the respective plural cells 10 are compared with a data base instructing states proper for the respective plural cells 10. When the step of comparison instructs the program state of any cell 10 is not proper, that cell 10 is programmed during 2nd time without simultaneously programming any other cells 10 inside the plural rows 15.</p> |
