a plurality of pixels arranged so as to form a plurality of rows and a plurality of columns;

a plurality of processing circuits; and

a control circuit configured to control the plurality of processing circuits,

wherein each of the plurality of processing circuits comprises a first column circuit and a second column circuit, each of which performs A/D conversion of converting, into a digital signal, a pixel signal output from the pixel arranged in a corresponding column of the plurality of columns,

wherein the control circuit comprises a generation circuit configured to generate a first signal used in the A/D conversion, and a second signal different from the first signal and used in the A/D conversion,

wherein the apparatus further comprises a selection circuit configured to receive the first signal and the second signal, and to select and supply one of the first signal and the second signal to the second column circuit in a period in which the first signal is supplied to the first column circuit,

wherein the first column circuit converts one pixel signal into a digital signal using the first signal, and

wherein the second column circuit converts the one pixel signal used in the first column circuit into a digital signal using the first signal or the second signal selected by the selection circuit.