Patent ID: 6614270
Filing Date: 2003-09-02
Classification: G11C,H02M

Abstract:
A semiconductor device for detecting whether a potential at a predetermined node is higher than a reference potential or not, comprising:a potential detecting circuit; a ring oscillator operating by receiving an output from said potential detecting circuit; and a charge pump circuit operating based on an output from the ring oscillator wherein a driving potential of said charge pump circuit is a first power supply potential, wherein the potential detecting circuit comprises: a first power supply potential node for receiving the first power supply potential; a second power supply potential node; a comparator for comparing the potential at said predetermined node with said reference potential and outputting a signal of first level or second level on the basis of a comparison result; and an inverter for receiving the output signal of said comparator and outputting an inversion signal of the output signal to an output node, wherein said inverter comprises: a first transistor of a first conduction type connected between said first power supply potential node and said output node, having an input electrode for receiving the output signal of said comparator; a second transistor of a second conduction type having a first electrode connected to said output node and an input electrode for receiving the output signal of said comparator; and a third transistor of the second conduction type connected between a second electrode of said second transistor and said second power supply potential node, having an input electrode connected directly to said first power supply potential node, wherein said first power supply potential node supplies a potential different from a potential of the second electrode of said second transistor.