Patent ID: 11910111
Assignee: AMS SENSORS BELGIUM BVBA
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A pixel cell comprising:
a pixel set with a plurality of pixels, with each pixel comprising a photodiode and a transfer gate coupled to the photodiode; and
a readout circuit comprising
a floating diffusion with an adjustable capacitance coupled to all of the transfer gates;
a column output line;
a sample-and-hold stage (SHS) coupled to the floating diffusion, the sample-and-hold-stage comprising a first storage stage and a second storage stage arranged in series or in parallel, each of the first and second storage stages comprising a switch and a capacitor that is coupled between the switch and a fixed potential;
a first switch coupling the sample-and-hold-stage to the column output line; and
a second switch coupling the floating diffusion to the column output line or to a further column output line,

 wherein
the readout circuit is configured to:
in a global shutter mode of operation, control the plurality of pixels such that corresponding charges generated by the photodiode of each of the plurality of pixels in response to incident radiation are simultaneously transferred to the floating diffusion in accordance with transfer control signals simultaneously transmitted to the transfer gates;
in a rolling shutter mode of operation, control the plurality of pixels such that corresponding charges generated by the photodiode of each of the plurality of pixels in response to incident radiation are sequentially transferred to the floating diffusion in accordance with transfer control signals sequentially transmitted to the transfer gates; and
adjust the capacitance of the floating diffusion such that the capacitance of the floating diffusion in the global shutter mode is larger than the capacitance of the floating diffusion in the rolling shutter mode;

wherein the pixel set is operated
in the global shutter mode for charges generated by the photodiode of each of the plurality of pixels based on incident radiation in a first wavelength range, wherein the first wavelength range is a near-infrared range; and
in the rolling shutter mode for charges generated by the photodiode of each of the plurality of pixels based on incident radiation in a second wavelength range;
wherein the capacitance of the floating diffusion in the global shutter mode is larger than the capacitance of the floating diffusion in the rolling shutter mode by a factor that is equal to the number of pixels in the pixel cell.