Pixels are used to sense incoming radiation. Non-limiting examples of such pixels include infrared pixels, visible light pixels and various other radiation sensitive pixels.
Some pixels operate in a current mode while some other pixels operate in a voltage mode. A pixel that operates in current mode outputs an output current while a pixel that operates in voltage mode outputs an output voltage.
Pixels that operate in current mode have higher photoresponse variations than pixels that operate in voltage mode—due to local variations of their output device transconductance. Due to these variations, most analog pixels operate at voltage mode although voltage mode is much slower than current mode.