残差时间计数型InGaAs脉冲频率调制数字读出电路研究  

Study of Residual-time-counting Pulse Frequency Modulation Digital Readout Circuit for Ingaas Focal Plane Array

作　　者：王绪泉 汪鸿祎 张永刚[1,2] 黄松垒[1,2] 方家熊(指导)[1,2] WANG Xuquan;WANG Hongyi;ZHANG Yonggang;HUANG Songlei;FANG Jiaxiong(State Key Laboratories of Transducer Technology,Shanghai Institute of Technical Physics,Chinese Academy of Sciences,Shanghai 200083,China;Key Laboratory of Infrared Imaging Materials and Detectors,Shanghai Institute of Technical Physics,Chinese Academy of Sciences,Shanghai 200083,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海技术物理研究所传感技术联合国家重点实验室,上海200083 [2]中国科学院上海技术物理研究所,中国科学院红外成像材料与器件重点实验室,上海200083 [3]中国科学院大学,北京100049

出　　处：《光子学报》2022年第5期271-278,共8页Acta Photonica Sinica

基　　金：国家自然科学基金(No.62175250),安徽省科技重大专项(No.S202003a06020001);传感技术联合国家重点实验室开放课题(No.SKT1907)。

摘　　要：为提高动态范围,提出一种针对InGaAs焦平面电容负反馈放大型输入级的残差时间计数型两步式脉冲频率调制数字读出电路。建立了电容负反馈放大型输入级的脉冲频率调制数字化理论转换模型,分析了积分电容残余电荷和复位遗失电荷引起的转换误差和线性度问题。基于0.18μm CMOS工艺设计了线列光谱组件用双积分电容残差时间计数型两步式脉冲频率调制数字化结构,改善了转换误差和线性度,实现了16位粗略转换与最大16位精细转换的融合,为短波红外光谱组件的野外复杂场景应用提供了一种大动态范围的数字读出方案。With the advantages of speediness,lossless and high-efficiency,the technology of Near-infrared(NIR)spectroscopy can be applied to the applications of composition analysis.In recent years,the development of portable micro-spectrometer and spectral sensing Internet of Things has promoted the application of spectral analysis technology to field analysis and online detection.The NIR spectral sensors with High Dynamic Range(HDR)and anti-interference capability are required.Digital Readout Circuit(DROIC)can optimize the quality of readout signal and improve the performance of NIR focal plane array effectively.Pulse Frequency Modulation(PFM)DROIC can convert the photocurrent of detector into digital pulses by resetting the integrating capacitor repeatedly in integrating period.PFM structure is a feasible technique for HDR DROIC,because it breaks the limitation of charge capacity determined by integrating capacitance and power supply voltage in conventional readout circuits.Due to process limitations,the residual charge on integrating capacitor after the last reset cycle can cause conversion errors.In addition,there are some problems such as poor linearity under strong light environment.Various methods have been proposed to resolve the problems of linearity and conversion errors.InGaAs Focal Plane Arrays(FPAs)have the advantages of working near-room temperature,high detection rate,good uniformity and stability,which is beneficial to realize the miniaturization design of the NIR photoelectric system.Most InGaAs detectors use the Capacitance Feedback Trans-impedance Amplifier(CTIA)input stage,but there are relatively few researches on the PFM ROIC of CTIA input stage currently.A two-step Residual-time-counting Pulse Frequency Modulation(RTC-PFM)DROIC was proposed for CTIA input stage of InGaAs FPAs to improve the dynamic range.The non-ideal reset of CTIA input stage in PFM DROIC is studied.The PFM conversion theory model of CTIA input stage is established.The conversion error caused by residual charges of integral capacito

关 键 词：读出电路 铟镓砷 脉冲频率调制 大动态范围 数字化 

分 类 号：TN215[电子电信—物理电子学]