Patent ID: 7990449
Filing Date: 2011-08-02
Classification: H01L,H04N

Abstract:
1. A semiconductor device comprising: a photo-conversion node; a first charge storage node configured to store charge generated by the photo-conversion node; a second charge storage node configured to store charge generated by the photo-conversion node when the charge exceeds a limit, wherein the limit is the charge storage capacity of the first charge storage node; a third charge storage node configured to store charge generated by the photo-conversion node when the charge exceeds the combined storage capacity of the first and second charge storage nodes; a transistor coupled between the first and second charge storage nodes and configured to transfer charge to the second charge storage node when the charge exceeds the limit; and a second transistor coupled between the second and third charge storage nodes and configured to transfer charge to the third charge storage node when the charge exceeds the combined storage capacity of the first and second charge storage nodes.