| 摘要 |
<P>PROBLEM TO BE SOLVED: To measure a time until the recovery of power supply from the shut-down of the power supply with no use of a battery for making contribution to the low-cost operation of a system LSI. <P>SOLUTION: The electronic timer comprises a parallel unit 10 constituted by connecting a plurality of aging devices in parallel, each of which is formed of a transistor including a floating gate and is turned on or off for a constant time by the accumulation of charges, a current detecting circuit 20 for detecting a total current flowing into the parallel unit 10 when a voltage is applied across input/output ends of the parallel unit 10, and a time measuring circuit 30 for measuring the time until the power supply recovers from the moment of shut-down on the basis of the detected total current. <P>COPYRIGHT: (C)2007,JPO&INPIT |
