Actuator driver

1. An image sensor comprising:

a pixel array comprising a plurality of pixels arranged in an image acquisition area;

a position detection coil arranged in an area that surrounds the image acquisition area; and

a readout control circuit structured to control the plurality of pixels, and to read out pixel values from the plurality of pixels,

wherein a lens is provided on an optical path of incident light to the image sensor,

wherein an induced electromotive force occurs in the position detection coil according to a magnetic field generated by a coil of an actuator structured to support positioning of the lens,

wherein the actuator is pulse drive, and wherein the readout control circuit generates a transmission permission signal that indicates whether transition of a pulse-shaped driving signal to be supplied to the coil of the actuator is to be permitted or prohibited,

wherein the pixel array and the position detection coil are integrated on a first chip, and

wherein the readout control circuit is integrated on a second chip having an upper face on which the first chip is mounted.

2. The image sensor according to claim 1 , wherein the lens is configured as an autofocus lens.

3. The image sensor according to claim 1 , further comprising an actuator driver structured to pulse drive the actuator such that a position detection signal that indicates a position of the lens matches a position instruction signal that indicates a target position of the lens,

wherein the actuator driver controls the pulse-shaped driving signal to be supplied to the actuator such that a transition occurs in the driving signal in a period in which the transmission permission signal indicates the permission for signal transition.

4. The image sensor according to claim 2 , further comprising a position detection circuit structured to generate a position detection signal that indicates a position of the lens based on the induced electromotive force that occurs in the position detection coil.

5. A camera module comprising an image sensor comprising:

a pixel array comprising a plurality of pixels;

a lens provided on an optical path of incident light to the image sensor;

an actuator comprising a coil, and structured to support positioning of the lens according to a driving signal applied to the coil;

a position detection coil arranged such that it magnetically couples with the coil of the actuator;

an actuator driver structured to supply the pulse-shaped driving signal to the coil of the actuator; and

a position detection circuit structured to generate a position detection signal that indicates a position of the lens based on an induced electromotive force that occurs in the position detection coil according to the driving signal, and to feed back the position detection signal to the actuator driver, wherein the position detection coil is built into the image sensor.

6. The camera module according to claim 5 , wherein the image sensor supplies a transition permission signal that indicates whether transition of the driving signal is to be permitted or prohibited, in synchronization with an internal operation.

7. An electronic device comprising the camera module according to claim 5 .

8. An actuator driver structured to drive an actuator structured to support positioning of a lens provided on an optical path of incident light to an image sensor, the actuator driver comprising:

an interface circuit structured to receive a position instruction signal that indicates a target position of the lens;

a controller structured to generate a control pulse with at least one variable property from among a duty ratio, frequency, on time, and off time, which is changed such that the position instruction signal matches a position detection signal obtained based on an induced electromotive force that occurs in a position detection coil arranged such that it magnetically couples with a coil included in the actuator; and

a driver unit structured to drive the actuator based on the control pulse,

wherein the position detection coil is built into the image sensor.

9. The actuator driver according to claim 8 , wherein the controller is structured to receive, from the image sensor, a transition permission signal that indicates whether transition of the control pulse is to be permitted or prohibited, and to apply the transition permission signal to the control pulse.