| 摘要 |
<p>PROBLEM TO BE SOLVED: To screen respectively and optimally a peripheral circuit and a memory area by applying a voltage to a memory element through a high voltage generation circuit and providing a switch circuit between the memory area and the peripheral circuit such as the high voltage generation circuit, etc., of an electrically rewritable device. SOLUTION: When the screening is performed, the switch 50 terminal T1 is connected to a terminal T3, and the high voltage generation circuit 30 is separated from a memory cell area 10, and a prescribed voltage is applied from an external input terminal to respective memory cells, and the memory cell area 10 is screened. Further, a prescribed load is applied to the peripheral circuit in the state separating the high voltage generation circuit 30 from the memory cell area 10 to screen the peripheral circuit. Thus, the screening is performed optimally. Then, since a device is shipped after the device is lowered to a prescribed instantaneous failure rate in an accidental failure interval also in either one between the memory cell area 10 and the peripheral circuit, a flash memory device with extremely high reliability becomes possible.</p> |
