Analog front-end circuit and electronic device

1. An analog front-end circuit that controls an imaging device and processes an analog image signal output from the imaging device, the analog front-end circuit comprising:

an analog processing section that receives an analog image signal from the imaging device, provides the image signal with predetermined processing, and outputs the image signal;

an A/D converter that performs A/D conversion with the image signal output from the analog processing section;

a transmitter circuit that receives digital image data output from the A/D converter, generates a differential signal based on the digital image data, and outputs the differential signal; and

a timing generator that generates a plurality of clocks including a multiphase driving clock for driving the imaging device based on a first reference clock;

the transmitter circuit including a differential amplifier circuit that generates a differential signal based on the digital image data output from the A/D converter, and outputting the differential signal generated in the differential amplifier circuit.

2. The analog front-end circuit according to claim 1 ,

the timing generator generating a transmission clock as a clock included in the plurality of clocks and outputs the transmission clock to the transmitter circuit; and

the transmitter circuit generating a differential signal based on the transmission clock, and generating a differential clock signal being a synchronizing clock of the differential signal that the transmitter circuit outputs.

3. The analog front-end circuit according to claim 1 , further comprising a PLL circuit that receives a second reference clock, generates a clock by multiplying a frequency of the second reference clock by N, and outputs the clock as the first reference clock.

4. The analog front-end circuit according to claim 3 , further comprising a receiver circuit that receives a reference clock differential signal, generates the second reference clock based on the reference clock differential signal received, and supplies the second reference clock to the PLL circuit.

5. The analog front-end circuit according to claim 4 , the receiver circuit receiving the reference clock differential signal through a connection cable connecting the transmitter circuit and a main board on which an image processing section processing image data output from the transmitter circuit is mounted from the main board.

6. The analog front-end circuit according to claim 1 , the timing generator generating an A/D converter clock that the A/D converter uses for performing A/D conversion, as a clock included in the plurality of clocks, and outputting the A/D converter clock to the A/D converter.

7. The analog front-end circuit according to claim 1 , the timing generator generating a timing control clock for the analog processing section, as a clock included in the plurality of clocks, and outputting the timing control clock to the analog processing section.

8. The analog front-end circuit according to claim 1 , the analog processing section performing correlated double sampling and amplifying as the certain processing.

9. The analog front-end circuit according to claim 1 ,

the timing generator including a clock pattern set register for setting clock patterns of the plurality of clocks; and

the timing generator generating the plurality of clocks with different clock patterns from the first reference clock based on a set value of the clock pattern set register.

10. The analog front-end circuit according to claim 9 ,

setting information of the clock pattern set register of the timing generator being set based on a control signal supplied from a main board on which the image processing section processing image data output from the transmitter circuit is mounted, and

the control signal being supplied by serial communication.

11. The analog front-end circuit according to claim 1 , the analog front-end circuit further including between the A/D converter and the transmitter circuit a selector that outputs the digital image data output from the A/D converter by using time division multiplexing,

the selector dividing the digital image data into data of a certain bit and sequentially outputting the data divided to the transmitter circuit by using time division multiplexing.

12. An electronic device, comprising:

a board for head on which the analog front-end circuit according to claim 1 and the imaging device are mounted;

a main board on which an image processing section processing image data output from the analog front-end circuit is mounted; and

a connection cable connecting the board for head and the main board;

the connection cable including a plurality of pairs of differential signal lines; and

image data output from the analog front-end circuit being transmitted by a differential signal through the connection cable.

13. The electronic device according to claim 12 , the plurality of driving clocks for driving the imaging device being supplied from the analog front-end circuit to the imaging device without passing through the connection cable.

14. The electronic device according to claim 12 , the main board including:

a differential signal receiver circuit that receives a differential signal transmitted through the connection cable; and

a differential signal transmitter circuit that transmits a reference clock through the connection cable to the board for head by using a differential signal.