| 摘要 |
PROBLEM TO BE SOLVED: To achieve miniaturization of an apparatus which can not be realized by an analog structure. SOLUTION: An A/D converter 10 is provided to perform a digital conversion of a terminal voltage of a capacitor 14 for smoothing the output of a bridge circuit 15 and a judging circuit 11 to judge deterioration of a capacitor 14 for smoothing based on the output of the A/D converter 10. The terminal voltage of the capacitor 14 is measured at small time interval to detect deterioration of the capacitor 14 from the gradient of the fluctuation in the voltage of a DC output. |
