| 摘要 |
<p>PURPOSE:To normally read out data even when a memory cell is over-erased by detecting electric charge and using a sense amplifier. CONSTITUTION:The information in an over-erased memory cell 11 whose electric charge is discharged more than a prescribed amount by erasing operation, is detected by a detecting means 12. The detecting means 12 outputs a loading changeover signal and inputs it to a changeover means 13. On the other hand, prior to erasing operation, the changeover means 13 is reset by a resetting means 14. Thus, the ability of a sense amplifier 25 is changed over by means of the loading changeover signal. The amplifier 25 reads data out of the erased memory cell 11.</p> |
