Patent ID: 7485836

Claim:
A method of operating pixels of an image sensor comprising: applying a first voltage to a photosensor to flood the photosensor with pre-charge electrons; applying a second voltage to the photosensor to drain a portion of the pre-charge electrons off the photosensor, where the second voltage is higher than the first voltage; accumulating photo-generated charge in the photosensor from an image to be captured by the image sensor; providing an operating voltage across a source follower transistor; setting a floating diffusion node, which is coupled to a gate of the source follower transistor, to a high reset voltage that exceeds a threshold turn-on voltage of the source follower transistor; turning on a transfer transistor to transfer a charge from the photosensor to the floating diffusion node, changing the charge at the floating diffusion node to a signal voltage; and reading a signal provided by the source follower transistor in response to the signal voltage.