一种用于CMOS图像传感器的Column-Level模数转换器  

A Novel Column-Level ADC for CMOS Image Sensor

作　　者：王亚杰[1] 姚素英[1] 徐江涛[1] 付贤松[1] 

机构地区：[1]天津大学ASIC设计中心,天津300072

出　　处：《光电子．激光》2006年第3期290-294,共5页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金资助项目(60576025);天津市重点科技攻关资助项目(033183911)

摘　　要：设计了一种用于CMOS图像传感器(CIS)的column-level模数转换器(ADC)。它由一种新型斜坡发生器构成,具有分辨率可调的特点,而且以简单的结构实现了高精度和低功耗,占用较小的版图面积。基于0.35μm2P4M标准CMOS工艺,8bit ADC转换时间约50μs,最大线性误差小于±0.5LSB。在分辨率为640×480pixel的CIS中,每列共用1个比较器,提高了传感器的吞吐速率,帧频约40fps;3.3V电压下ADC总功耗不超过27mW,占用版图面积约0.5mm2。A column-level analog to digital converter（ADC） with a novel ramp generator is presented. The ADC is suitable for video applications,especially for CMOS image sensors （CIS）. With the novel structure, the resolution of the ADC is adjustable;meanwhile the ADC has higher precision, lower power dissipation and uses less chip area. It has been designed in 0.35μm 2P4M standard CMOS process. For 8 bit resolution,the conversion time is about 50 μs,and the maximum measured linearity error is less than ±0.5 LSB. A CIS with 640× 480 pixels increases the throughput with one comparator dedicated to one column of the pixel arrays,and the continuous frame rate is about 40 fps. With a 3.3 V power supply the ADO of the sensor dissipates less than 27 mW,and its die area is about 0.5 mm^2.

关 键 词：CMOS图像传感(CIS) coluilln-level模数转换器(ADC) 斜坡发生器 比较器 

分 类 号：TN402[电子电信—微电子学与固体电子学]