Patent ID: 9571774
Date: 2017-02-14
CPC Classifications: H04N

Claim:
1. A device comprising a pixel, a current source, and a readout circuit; wherein during a first readout phase of the pixel, the readout circuit is configured to sample a sampled output voltage of an output node of the pixel; and wherein an output current of the pixel is set by the current source; wherein between the first readout phase of the pixel and a second readout phase of the pixel, the pixel is configured to change the output current to provide a second output current, wherein the change of the output current is responsive to radiation sensed by a radiation sensor of the pixel during a sensing period; wherein during the second readout phase of the pixel the readout circuit is configured to sample the second output current while providing the sampled output voltage to the output node of the pixel; wherein during the first readout phase of the pixel and the second readout phase of the pixel a drain source voltage of an output transistor of the pixel is maintained constant; and wherein the output transistor is configured to generate the second output current.