Patent ID: 8441563

Claim:
A photoelectric conversion device comprising: a pixel array that includes a plurality of pixels arranged two-dimensionally, each of the plurality of pixels having a photoelectric conversion element, the pixel array outputting a pixel signal in accordance with an incident light amount to the photoelectric conversion element; and a plurality of A/D converters each of which includes a pulse delay circuit and an encoder, the pulse delay circuit including a plurality of delay units, each of the plurality of delay units delaying a pulse signal with a delay time that is based on the difference between a voltage of the pixel signal, which is received from the pixel array, and a reference voltage, the plurality of delay units being connected so that the pulse signal can circulate through the plurality of delay units, the encoder outputting a digital value based on the number of the plurality of delay units that the pulse signal passes through within a predetermined period of time, and wherein the encoder comprising: a latch circuit that includes a plurality of latch units each of which corresponds to the plurality of delay units, each of the plurality of latch units storing delay information, the delay information being output when the pulse signal passes through each of the plurality of delay units; an encoder unit that outputs the digital value based on the delay information; and a counter unit that counts the number of circulations of the pulse signal passing through the plurality of delay units within a predetermined period of time, the counter unit outputting the digital value based on the number of circulations, wherein each of the plurality of delay units and each of the plurality of latch units corresponding to each of the plurality of delay units are arranged adjacently in a first direction of the pixel array to configure each of a plurality of delay detectors, wherein the plurality of delay detectors are arranged adjacently in the first direction, and wherein a reference voltage wire that supplies the reference voltage to each of the plurality of A/D converters is branched to be a plurality of branched reference voltage wires, each of the plurality of branched reference voltage wires corresponds to each constituent component in the plurality of A/D converters, and each of the plurality of branched reference voltage wires is connected to a corresponding constituent component in the plurality of A/D converters.