| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor device having high reliability for operation by solving such a problem that when a voltage step-down circuit is mounted in a flash memory, after applying an external power source, sometimes, internal power source voltage is not raised to a desired level. <P>SOLUTION: In this semiconductor device, a reset signal generating circuit 5 makes an output reset signal RSA a "L" level in a period from applying the external power source voltage to that internal power source voltage reaches the prescribed value. In this period, a voltage level of an output signal of a level shifter 3 becomes an unpredictable value, but a zero standby mode signal STBYZ11 from an AND circuit 8 is made the "L" level. A voltage step-down circuit 9 raises the internal power source voltage to a desired level in accordance with that the zero standby mode signal STBYZ 11 is made the "L" level. Therefore, when the external power source voltage is applied, the internal power source voltage is raised surely to the desired level. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
