| 摘要 |
PROBLEM TO BE SOLVED: To eliminate a trouble of low resolution due to the limitation, etc., of a feedback signal from a dynamic range, by converting the feedback signal of plural analog values from a high voltage output part supplied to each roller, etc., from AC to DC within a high voltage control LSI so as to control it digitally. SOLUTION: A plurality of analog inputs are inputted into terminals of ch0 to ch9. A plurality of analog switches 21 are switched in order, and a A/D converter 22 converts the analog values of ch0 to ch9 into digital. The feedback signal converted into digital is transferred to a comparator 23. The set value stored in a set value register 24 is stored, corresponding to analog input 28, and each time the analog input 28 is A/D-converted with an A/D converter 22, a selector 25 selects the set value corresponding to each ch and transfers it to a comparator 23. The comparator 23 compares the output of the A/D converter 22 with the set value corresponding to its ch to check the magnitude, and stores the comparison result in a register 26. |
