ANALOG-DIGITAL CONVERTER AND SOLID STATE IMAGE PICKUP DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an analog-digital converter and a solid state image pickup device that reduce power consumption.SOLUTION: The analog-digital converter comprises: a reference signal generation section 104 for outputting as a reference signal either or both of a first signal decreasing with time and a second signal increasing with time; a comparison/conversion section 110 for comparing an input analog signal with the reference signal, and outputting a digital value corresponding to a comparison time from when the comparison process is started to when the reference signal satisfies a predetermined condition relative to the analog signal; an arithmetic processing section 108 for generating a digital signal corresponding to the input analog signal on the basis of the digital value, and outputting the generated digital signal; and a control section 199 for switching the reference signal input into the comparison/conversion section to either the first signal or the second signal such that the comparison time for the input analog signal is shortened.