| 摘要 |
PROBLEM TO BE SOLVED: To easily control a charging voltage and a charging current, by connecting a connecting node to a feedback end of switching mode power supply through the line, connecting a first voltage output port of digital-analog conversion means to the line, and connecting a detected current output port to a second voltage output port of digital-analog conversion means while connecting the detected current output port to the line. SOLUTION: An operation power supply required for a charging circuit based on input power supply is achieved by controlling an SMPS 10 with a PWM controller 11 so as to keep a voltage applied to a feedback end FB constant. Output level of drive signal output ends DH, DL is set to L, H respectively, thereby preventing an overcurrent flowing through the primary coil of a transformer 12. Then, the quantity of current output through an output port OUT is controlled through a current detector 30, thereby permitting a selective control of charging current and voltage based on a power supply voltage output from a digital-analog converter 50. |
