Charge detection node with variable conversion gain and kTC noise suppression

摘要

The Floating Diffusion charge detection system has incorporated a signal feedback directly into the charge-detection node. The feedback is coupled to the node from the output of the standard buffer amplifier A1 through a feedback amplifier A3, switching transistors S2 and S3, and capacitors Cf and Ch. The feedback significantly reduces kTC noise, has good linearity, and improves DR.