DRIVE CONTROL CIRCUIT AND FOCUS CONTROL CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a drive control circuit and a focus control circuit capable of reducing the noise resulting from PWM drive current.

SOLUTION: An equalizer 30 generates a control signal for matching the state of the object with the target value based on the difference between the targeted value and the actual measurement value concerning the state of the object. A PWM modulation part 40 generates the PWM signal corresponding to the control signal generated by the equalizer 30. An H-bridge drive part 50 generates the drive current for driving a drive element 12 which changes the state of the object according to the PWM signal generated by the PWM modulation part 40. A slew-rate control part 60 changes the current drive capability of the H-bridge drive part 50 according to the control signal.

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