| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To satisfy both the stable operation of a semiconductor device and the highly precise detection of the abnormality of a power supply voltage and a substrate voltage, and to minimize any damage due to an erroneous operation due to the abnormality. <P>SOLUTION: The semiconductor device 100 is provided with: a CPU part 10 to which a prescribed power supply voltage VDD and a substrate voltage VBB are supplied; and a first abnormality detection part 13 and a second abnormality detection part 20 for detecting the abnormality of the power supply voltage VDD and the substrate voltage VBB. The second abnormality detection part 20 is provided with a ring oscillator 21 and a monitoring part 22 for monitoring the output frequency of the ring oscillator 21. The power supply voltage VDD and the substrate voltage VBB are supplied to the ring oscillator 21, and the output frequency changes according to the power supply voltage VDD and the substrate voltage VBB. The monitoring part 22 outputs a warning signal showing abnormality when the output frequency of the ring oscillator 21 deviates from a prescribed range. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
