Solid-state imaging device with high resolution A/D conversion

A solid-state imaging device comprising:

• pixels;
• a charge storage capacitor that temporarily stores voltage values of pixel output signals that are outputted from the pixels;
• a comparison signal generator that generates comparison signals having voltage values that vary in a certain range from an upper limit to a lower limit with time;
• and
• a first analog-to-digital converter circuit that performs analog-to-digital conversion by comparing the voltage values that are stored in the charge storage capacitor with the comparison signals,
• wherein the comparison signal generator generates the comparison signals such that a waveform having a voltage value that ranges from the upper limit to the lower limit and that has linearity and continuity between the upper limit and the lower limit is formed by connecting waveforms that represent variation in the voltage values of the comparison signals with time to each other,
• wherein the solid-state imaging device further comprising:
• a reference voltage generator that generates a reference voltage having a voltage value of both of two of the comparison signals having voltage values that partly overlap;
• and
• a second analog-to-digital converter circuit that performs analog-to-digital conversion by comparing the voltage value of the reference voltage with the comparison signals.