Solid-state imaging device, imaging apparatus, and ad conversion gain adjusting method

A solid-state imaging device comprising:

• a pixel unit in which unit pixels that output analog processing target signals are arranged in a horizontal direction and scanning lines are wired such that the analog processing target signals can be read out in order in a vertical direction within a repetition unit of an array of the unit pixels in the horizontal direction;
• a single reference-signal generating unit that generates a reference signal having a gradually changing level, the reference-signal generating unit including one digital to analog (DA) conversion unit;
• an analog to digital (AD) conversion unit including (i) comparing units that compare (a) the reference signal having a gradually changing level supplied from the reference-signal generating unit and (b) the analog processing target signals, and (ii) counter units that receive supply of a count clock for AD conversion and perform count operation in a count operation effective period based on comparison results of the comparing units, the AD conversion unit performing AD conversion processing to acquire digital data of the analog processing target signals on the basis of output data of the counter units;
• and
• a driving control unit that (i) performs control to read out the analog processing target signals in order in the vertical direction within the repetition unit of the array of the unit pixels in the horizontal direction of the pixel unit and (ii) is configured to control the reference-signal generating unit and the AD conversion unit during the AD conversion processing such that AD conversion gains indicating size of the output data of the counter units with respect to the analog processing target signals are individually adjusted according to color information of the analog processing target signals in order to correct an output amplitude characteristic difference among the unit pixels within the repetition unit for white balance adjustment during the AD conversion processing, the driving control unit including a communication/timing control unit that controls the reference-signal generating unit and the AD conversion unit based on gain control information that (a) is provided to the communication/timing control unit by a digital processing unit separate from the communication/timing control unit and that (b) indicates a gain value desired to be adjusted for each color.