Patent ID: 8675107

Claim:
A photoelectric conversion apparatus comprising: a vertical output line; a pixel including a photoelectric conversion unit configured to convert light into charges and to store the charges, an amplifying unit configured to output a signal corresponding to the charges stored in the photoelectric conversion unit to the vertical output line, and a reset unit configured to reset an input of the amplifying unit; a current source load electrically connected to the vertical output line, wherein a source follower is constituted by the amplifying unit of the pixel and the current source load; and a clip unit electrically connected to the vertical output line so as to limit a voltage of the vertical output line, wherein the clip unit includes: amplifying circuitry configured to amplify a signal corresponding to the electric voltage of the vertical output line, and a MOS transistor configured to limit the electric voltage of the vertical output line based on a difference in electric potential between gate and source of the MOS transistor, wherein the amplifying circuitry includes an operational amplifier with an inverting input terminal connected to the vertical output line, a noninverting input terminal to which a predetermined voltage is applied, and an output terminal connected to the gate of the MOS transistor, and wherein the clip unit further includes a control unit configured to apply the predetermined voltage to the noninverting input terminal, wherein the control unit applies a first voltage as the predetermined voltage to the noninverting input terminal when a reset level set by the reset unit is read out to the vertical output line, and wherein the control unit applies a second voltage, which is lower than the first voltage, as the predetermined voltage to the noninverting input terminal when a signal based on the electrical charges stored in the photoelectric conversion unit is read out to the vertical output line.