A photoelectric conversion device and a method of driving the same according to a third embodiment of the present invention will be described with reference to FIG. 7 and FIG. 8. FIG. 7 is a block diagram illustrating a general configuration of the photoelectric conversion device according to the present embodiment. FIG. 8 is a timing diagram illustrating a readout operation in the photoelectric conversion device of the present embodiment. The same components as those in the photoelectric conversion devices according to the first and second embodiments are labeled with the same reference, and the description thereof will be omitted or simplified.