| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage conversion device that seamlessly switches between step-down conversion and step-up conversion independently of a voltage drop by circuit elements and temperature changes in and variations in the circuit elements.SOLUTION: The voltage conversion device includes: a step-down PWM signal creation circuit 8 for detecting a difference between an output voltage stepped down from an input voltage and a step-down target voltage, and creating a PWM signal for PWM-controlling a step-down switching element 2 on the basis of the detected difference; a step-up PWM signal creation circuit 7 for detecting a difference between an output voltage stepped up from the input voltage and a step-up target voltage, and creating a PWM signal for PWM-controlling a step-up switching element 3 on the basis of the detected difference; and means 10 for bringing the step-down target voltage, which is a control target of the step-down PWM signal creation circuit 8, higher than the step-up target voltage, which is a control target of the step-up PWM signal creation circuit 7, by a predetermined level. |
