Patent ID: 8824255

Claim:
A multi-output power supply device comprising: a first power supply arranged to output a first output voltage; a second power supply arranged to output a second output voltage; a third power supply arranged to output a third output voltage; and a reset circuit arranged to monitor both the first output voltage and the third output voltage to detect an abnormality in each of the first output voltage and the third output voltage, and to output a first reset signal for forcibly stopping the output operation of the second power supply, wherein the reset circuit is provided apart from the first power supply, the second power supply, and the third power supply, and the reset circuit includes: an output abnormality detecting section arranged to output the first reset signal in accordance with the first output voltage and the third output voltage; and a timer arranged to output a second reset signal to both the first power supply and the third power supply after a predetermined period of time has elapsed since the input of the first reset signal, wherein the first power supply and the third power supply are both step-down DC/DC converters, and the second power supply is a step-up DC/DC converter, and the multi-output power supply device comprises, as circuit elements forming the first power supply, the second power supply, and the third power supply: a sawtooth wave generating circuit for outputting a first sawtooth wave, a second sawtooth wave, and a third sawtooth wave; a bias circuit for generating a first reference voltage, a second reference voltage, and a third reference voltage; a first error amplifier for amplifying error between the first output voltage and the first reference voltage; a first control drive section for comparing the output of the first error amplifier to the first sawtooth wave, and for outputting the first output voltage based on the results of the comparison; a second error amplifier for amplifying the error between the second output voltage and the second reference voltage; a second control drive section for comparing the output of the second error amplifier to the second sawtooth wave, and for outputting the second output voltage based on the results of the comparison; a third error amplifier for amplifying the error between the third output voltage and the third reference voltage; and a third control drive section for comparing the output of the third error amplifier to the third sawtooth wave, and for outputting the third output voltage based on the results of the comparison.