AD CONVERTER, AD CONVERSION DEVICE, PHOTOELECTRIC CONVERSION DEVICE, IMAGING SYSTEM, AND AD CONVERSION METHOD

摘要

PROBLEM TO BE SOLVED: To solve such problems that the dynamic range may be insufficient for the amount of incident light, and power consumption may increase.SOLUTION: When the magnitude of an analog signal goes below a threshold, a digital signal of p-bits is obtained by comparing the analog signal with a first reference signal by means of a comparator. When the magnitude of an analog signal goes above a threshold, a digital signal of q-bits smaller than the p-bits is obtained by comparing the analog signal with a second reference signal, having a rate of change with respect to the time larger than that of the first reference signal, by means of a comparator.