Actuator driver and its control method, camera module using the same, electronic device

Abstract

To provide an actuator driver capable of reducing power consumption or controlling decrease in reliability in a situation in which obstacles exist within a movable range.SOLUTION: An error detector 232 generates an error signal err between a position instruction PREF and a feedback signal PFB for showing a position of a movable part. A compensator 234 generates a control signal ctrl according to an error error. A clamp circuit 236 clamps the control signal ctrl so as to be within a tolerance and generates a clamp control signal ctrl'. A drive part 220 applies a drive signal corresponding to the clamp control signal ctrl' to a voice coil motor. A protection circuit 238A monitors the control signal ctrl inputted to the clamp circuit 236, and narrows the tolerance of the clamp circuit 236 when a state in which the control signal ctrl deviates from a predetermined range continues for predetermined time.SELECTED DRAWING: Figure 3

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