To provide a correlated double sampling (CDS) and analog/digital conversion (ADC) apparatus for an image sensor.

The present apparatus includes: a sampling unit which samples N (N1) times a pixel signal outputted from a predetermined pixel in order to generate signals on which first sampling is performed within a horizontal scan period, in an image sensor; a ramp signal generator which generates a ramp signal having a ramping portion for the first sampled signals; a comparison unit which compares each of the first sampled signals with the ramping portions in order to generate comparison signals, respectively; and a code generator for generating digital codes from the comparison signals.