| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage detection circuit for detecting a negative voltage, without using a negative power source. SOLUTION: This voltage detection circuit is equipped with a constant-current circuit, a differential circuit for outputting the comparison result between the first voltage and the second voltage by using the constant-current circuit as a current source, and an output circuit for outputting one logic voltage or the other logic voltage, corresponding to the comparison result by the differential circuit. The voltage detection circuit is also equipped with the first resistance group for setting the first voltage, by dividing the differential voltage between a positive reference voltage VREF and an input voltage VIN, and the second resistance group for setting the second voltage, by dividing a differential voltage between the reference voltage VREF and a fixed voltage VS. Resistance values of the first resistance group and the second resistance group are values for setting the first voltage and the second voltage, when the input voltage VIN is a specific negative voltage at the same voltage value. COPYRIGHT: (C)2005,JPO&NCIPI
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