Patent ID: 8068155

Claim:
A solid-state image sensor, comprising: photodiodes arranged in a matrix to form pixels, for generating signal charge according to intensity of incident light, and accumulating the generated signal charge therein; floating diffusions for holding the signal charge transferred from a corresponding one of the photodiodes; transfer transistors, each provided between a corresponding one of the photodiodes and a corresponding one of the floating diffusions; reset transistors, each having its drain connected to a power supply signal line, and its source connected to a corresponding one of the floating diffusions, for resetting the corresponding floating diffusion to a predetermined voltage; amplifying transistors for reading a voltage of a corresponding one of the floating diffusions; vertical signal lines provided in each column of the pixels, for receiving a signal from corresponding ones of the pixels; load transistors, each connected to a corresponding one of the vertical signal lines, and each forming a source follower circuit, together with a corresponding one of the amplifying transistors; clamp capacitors, each having a first terminal connected to a corresponding one of the vertical signal lines; sampling capacitors, each connected to a second terminal of a corresponding one of the clamp capacitors; clamp transistors, each having its drain connected to a first reference voltage, and its source connected to a corresponding one of the sampling capacitors; voltage comparison circuits, each connected in series with a corresponding one of the vertical signal lines; and clip circuits for outputting a clip voltage to a corresponding one of the sampling capacitors based on an output of a corresponding one of the voltage comparison circuits.