Patent ID: 7777170

Claim:
A solid-state imaging device comprising: a pixel array in which a plurality of pixels are arranged in rows and columns; a reference signal generation unit operable to generate a reference signal for each of horizontal periods, the reference signal changing monotonically for a predetermined period included in each of the horizontal periods; comparators that are arranged in one-to-one correspondence with the columns of the pixel array, each of the comparators being operable to compare, for each pixel in a corresponding column, (i) a level of a pixel signal output from a pixel in the corresponding column with (ii) a level of the reference signal; a counter operable to count input clock pulses; and a clock control unit operable to generate a clock that is to be input into the counter, and change frequency of the clock based on external input data, wherein the external input data indicates a brightness of a scene derived from a level of each of the pixel signals that have been output from the pixels, and the clock control unit changes the frequency of the clock in a manner that the brighter the brightness of the scene is, the lower the frequency of the clock is.