US Patent 11509852 Imaging device, imaging system, and method of driving imaging device

The imaging device includes a pixel including a photoelectric converter, a first switch, a charge holding portion, and an output unit, an output line, a readout circuit unit connected to the output line, and a control unit. The readout circuit unit includes an amplifier circuit, a second switch between the output line and the amplifier circuit, and a comparator comparing the amplified pixel signal with a reference signal. The control unit performs outputting a pixel signal by transferring the charge in the photoelectric converter to the charge holding portion, determining a level of the pixel signal amplified by the amplifier circuit, and setting a gain of the amplifier circuit in accordance with a result of determination, and sets the second switch to off during the first switch is in on and until the output unit is settled after the first switch transitions from on to off.