CCD低噪声读出电路设计  

Design of CCD low-noise readout circuit

作　　者：狄腊梅 刘宏[2] 张志勇[1] DI Lamei;LIU Hong;ZHANG Zhiyong(College of Information Science and Technology,Northwest University,Xi’an 710127,China;CAS Key Laboratory of Spectral Imaging Technology,Xi’an Institute of Optics and Precision Mechanics of CAS,Xi’an 710119,China)

机构地区：[1]西北大学信息科学与技术学院,陕西西安710127 [2]中国科学院西安光学精密机械研究所,光谱成像技术中科院重点实验室,陕西西安710119

出　　处：《现代电子技术》2019年第20期1-4,8,共5页Modern Electronics Technique

基　　金：国家自然科学基金面上项目资助(11573058);国家重点研发计划重点专项资助(2016YFC0201102)

摘　　要：以红外增强型图像传感器TH7888A所得的微弱电压信号为输入,对图像传感器的模拟前端处理电路进行设计。采用巴特沃斯低通滤波器和全差分双相关采样的方法,提高整体电路的信噪比为67 dB,从而减少了后续电路的输入噪声。使用Proteus对所设计的低噪声、高增益放大电路的功能和噪声分析等特性进行全面的实验。实验结果表明,该设计能有效放大微弱电压信号,并可以对放大的电压信号进行准确的相关双采样去除KTC噪声、复位噪声。最后,在实际应用中,使用FPGA为硬件设计载体,以vivado作为软件开发环境,使用Verilog语言对时序发生器进行了硬件描述。FPGA生成的模拟信号分别作为读出电路的输入和采样的触发信号,并验证了其正确性和可行性。An analog front?end processing circuit of the image sensor is designed,which takes the weak voltage signal re?ceived by infrared enhanced image sensor TH7888A as its input signal.The signal?to?noise ratio of the overall circuit is in?creased to 67 dB by means of the Butterworth low?pass filter and fully differential double?correlation sampling method to reduce the input noise of subsequent circuits.The comprehensive experiment was performed on the function and noise analysis of the de?signed low?noise high?gain amplification circuit by means of Proteus.The experimental results show this design can effectively amplify the weak voltage signal,and achieve the accurately correlate double sampling of the amplified voltage signal to remove the KTC noise and reset noise.In practical applications,FPGA is used as the hardware design carrier,the Vivado is used as the software development environment,and the Verilog language is used to perform hardware description of the timing generator.The analog signal generated by the FPGA is used as the input signal of readout circuit and the trigger signal of sampling respec?tively.Its correctness and feasibility are verified.

关 键 词：CCD 读出电路 FPGA 模拟前端 信号采样 数据分析 

分 类 号：TN722.3?34[电子电信—电路与系统] TP301.6[自动化与计算机技术—计算机系统结构]