Patent ID: 7271504
Filing Date: 2007-09-18
Classification: G06F,H03K

Abstract:
1. A semiconductor device which operates an internal circuit based on first and second power supply potentials different from each other, comprising: a first determination circuit which determines whether or not said first power supply potential is higher than a first reference potential; a second determination circuit which determines whether or not said second power supply potential is higher than a second reference potential; a third determination circuit which determines whether or not said first power supply potential is higher than said second power supply potential; a fourth determination circuit which determinates whether or not said second power supply potential is larger than a voltage value obtained by multiplying a prescribed value which is larger than 0 and less than 1 by said first power supply potential; and a power supply voltage control circuit which operates said internal circuit based on said first and second power supply potentials if all the determinations by said first, second, third and fourth determination circuits are “yes”, and outputs a signal for initializing said internal circuit if the determination by at least one of said first, second, third and fourth determination circuits is “no” in order to stop the operation of said internal circuit when at least one of said first and second power supply potentials instantaneously stops or breaks, or potential levels of said first and second power supply potentials are inverted.