Patent ID: 7619671
Filing Date: 2009-11-17
Classification: H04N

Abstract:
1. A method of operating a pixel of an image sensor, said pixel having a reset transistor having a first source/drain terminal coupled to a charge storage node which receives photogenerated charges and a second source/drain terminal for receiving a reset supply voltage, said method comprising: providing a reset supply voltage to said second source/drain terminal of the reset transistor; collecting charge in a pinned photodiode; pulsing a signal at a gate of the reset transistor to a voltage greater than a reset transistor threshold voltage causing said charge storage node to be reset; and after said pulsing maintaining a positive voltage level at the reset transistor gate during at least a portion of a pixel readout period, said positive voltage level not exceeding a voltage representing the maximum charge which can be stored at said charge storage node, and said positive voltage level not exceeding an approximate value of the voltage level of the reset voltage minus a value which is a pinning voltage of the photodiode multiplied by a value of a capacitance of the photodiode divided by a capacitance of the charge storage node.