提出了一种基于6T像素结构的全局曝光CMOS图像传感器。通过采用PPD结构的6T像素、高复位电平和低阈值器件, 提高了动态范围, 并优化设计了像素单元的版图, 使之获得较高的填充系数; 模拟读出电路部分, 通过采用双采样、增益放大和减小列级固定模式噪声(FPN)处理, 以及对列选控制电路进行优化, 减小了对全局PGA的运放设计要求。芯片的工作频率为20MHz, 动态范围为66dB, 实现了全局曝光方式CMOS图像传感器的设计。

A global exposure CMOS image sensor based on a 6T pixel structure was proposed. By adopting the devices with the structure of PPD 6T pixel, high reset level and low threshold, the dynamic range was improved, and higher fill factor was obtained by optimizing layout of the pixel. Analog readout circuit applies the process of double sampling, gain amplification and reduction of fixed pattern noise (FPN) of the column level. The column selection control circuit is optimized. The chip realizes a clock frequency of 20MHz and a dynamic range of 66dB, achieving the design of CMOS image sensor with global exposure.