应用于图像传感器的低功耗可编程增益放大器设计技术研究  

Research on Low Power PGA Design Method for Image Sensors

作　　者：郭仲杰 胡轩瑜 郭优美 王艺哲 GUO Zhongjie;HU Xuanyu;GUO Youmei;WANG Yizhe(School of Automation and Information Engineering,Xi'an University of Technology,Xi'an,710048,CHN)

机构地区：[1]西安理工大学自动化与信息工程学院,西安710048

出　　处：《固体电子学研究与进展》2025年第1期67-74,共8页Research & Progress of SSE

基　　金：国家自然科学基金面上项目(62171367);陕西省创新能力支撑计划项目(2022TD-39)。

摘　　要：为了降低超大面阵CMOS图像传感器芯片的平均功耗,基于开关电容放大器的工作机理,提出了一种针对图像传感器前端信号采集与放大模块功耗降低的方法。研究图像传感器光电信号的建立特征,分析信号稳定与偏置电流之间的动态关系,提出以信号高效建立为目标的动态低功耗偏置方法。针对功耗与速度的矛盾问题,提出采用跟随数模转换器(Digital-to-analog converter, DAC)的预置电压改进方法,在降低功耗的同时,提升了速度和精度。该方法已成功应用于一款3.3 V 55 nm CMOS工艺的2 048×2 048阵列规模CMOS图像传感器,完成了具体电路设计与后端物理实现。考虑寄生参数的后仿真验证结果表明,输出电压建立精度为12 bit,输出最大摆幅可到1.6 V,在500帧/秒的高速应用下,单列功耗仅有15.2μW,同时可实现1~4倍的可编程增益,与传统固定偏置方法比较,功耗降低了40%,为高速低功耗的高端超大面阵CMOS图像传感器的设计提供了理论基础。In order to reduce the average power consumption of large area array CMOS image sensor chip,based on the working mechanism of switched capacitor amplifier,a method to reduce the power consumption of image sensor front-end signal acquisition and amplification module was pro-posed in this paper.The establishment characteristics of photoelectric signal of image sensor were stud-ied,the dynamic relationship between signal stability and bias current was analyzed,and a dynamic low-power bias method aiming at efficient signal establishment was proposed.In view of the contradic-tion between power consumption and speed,an improvement method based on the preset voltage fol-lowing the digital-to-analog converter(DAC)was proposed,which not only reduced power consump-tion,but also improved speed and accuracy.This method has been successfully applied to a 2048×2048 array scale CMOS image sensor with 3.3 V 55 nm CMOS process,and completed specific cir-cuit design and backend physical implementation.The test results show that the output voltage estab-lishment accuracy is 12 bit,the maximum output swing can reach 1.6 V,and the single-column power consumption is only 15.2μW in the 500 frames/s high-speed application.At the same time,it can achieve 1-4 times of programmable gain.Compared with the traditional method using the fixed bias cir-cuit,the power consumption is reduced by 40%,which provides a theoretical basis for the design of high-speed,low-power and high-end CMOS image sensor with ultra large area array.

关 键 词：图像传感器 可编程增益放大器 低功耗 开关电容 

分 类 号：TN43[电子电信—微电子学与固体电子学]