| 摘要 |
PROBLEM TO BE SOLVED: To provide a power-supply voltage level detector which senses the difference between a reference voltage and a comparison voltage and which can detect a voltage at a desired level. SOLUTION: The power-supply voltage level detector is composed of a reference-voltage generation part which generates the reference voltage at a definite level according to a control signal, a comparison-voltage generation part which generates the comparison voltage at a rate of change larger than that of a power-supply voltage to be supplied from the outside according to a control signal and a comparison part which compares the reference voltage with the comparison voltage according to the control signal and which outputs a prescribed signal. The comparison-voltage generation part is composed of a first PMOS transistor which is operated according to the control signal and whose source is connected to the power-supply voltage, a resistance which is connected across the drain of the first PMOS transistor and a node, a second PMOS transistor which is connected across the power-supply voltage and an output terminal and which is operated according to the control signal and an NMOS transistor which is connected across the output terminal and a ground and whose gate is connected to the node. COPYRIGHT: (C)2003,JPO
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