基于CMOS图像传感器的大动态微弱信号检测电路设计  

Design of large dynamic weak signal detection circuit based on CMOS image sensor

作　　者：刘聪 罗向东[1] 王伟明 牛光珊 LIU Cong;LUO Xiangdong;WANG Weiming;NIU Guangshan(School of Information Science and Technology,Nantong University,Nantong 226019,China)

机构地区：[1]南通大学信息科学技术学院,江苏南通226019

出　　处：《现代电子技术》2022年第6期21-28,共8页Modern Electronics Technique

基　　金：国家自然科学基金资助项目(61927806);国家自然科学基金资助项目(61474067)。

摘　　要：为获得二维材料混合信号中微弱的调制信号,文中基于具有弱信号检测能力和大动态范围的CMOS图像传感器芯片S10122,选用ADI公司16位精度的LTC2204芯片和LTC1668芯片,使用两次采样模数转换(ADC)的方法设计一个大动态微弱信号检测电路。该电路在保证采样速率的前提下,可将16位ADC精度提高到18位,且采样速率达到20 MSPS。测试结果表明:文中电路能够有效地检测出微弱信号,且信号幅值随光强变化而变化。传感器采集到的信号能够通过USB模块有效传输至上位机,传输速率达到38.6 MB/s,实现了低精度ADC对微弱信号的高精度测量,满足实际探测需求。文中设计的两次采样电路具有电路结构简单、成本低、噪声干扰小的特点,与现有采样方法相比,具有更高的采样精度和速度,可为微弱信号的快速、高精度检测提供一种研究方向。Based on CMOS image sensor ship S10122 with weak signal detection capability and large dynamic range,the 16⁃bit chip LTC2204 and chip LTC1668 of ADI company are selected,and the twice⁃sampling ADC(analog to digital convertion)method is used to design large dynamic weak signal detection circuit to obtain the weak modulation signal in the mixed signal of two⁃dimensional materials.Under the premise of ensuring the sampling rate,this circuit can improve the accuracy of the 16⁃bit ADC to 18 bits with the sampling rate of 20 MSPS.The testing results show that the circuit designed in this paper can detect weak signals effectively,and the signal amplitude can change with the change of light intensity.The signal collected by sensor can be transmitted to the host computer effectively by means of USB module with the transmission rate of 38.6 MB/s,which realizes the high⁃precision measurement of weak signals by low⁃precision ADC,and meets the actual detection requirements.The twice⁃sampling circuit designed in this paper has the characteristics of simple circuit structure,low cost and low noise interference,and has higher sampling accuracy and speed compared with existing sampling methods,which can provide a research direction for the detection of the high⁃speed and high⁃precision weak signals.

关 键 词：检测电路 微弱信号检测 CMOS图像传感器 电路设计 两次采样电路 信号调制 模数转换 

分 类 号：TN792-34[电子电信—电路与系统]