背照CCD驱动电路技术研究

Research on the technology of back illuminated CCD driving circuit

为了满足微光遥感的低噪声探测要求,采用了英国E2V公司的背照式帧转移面阵CCD,设计了一套用于微光成像的视频电子学系统,给出了系统中电路的组成部分。为了获得良好的信号质量,围绕噪声主要组成成分,设计了用于微光成像系统的背照面阵CCD驱动电路及相关电路,有效地抑制了CCD的暗电流噪声和视频电路噪声。成像系统采用了Xilinx公司的Virtex-II型现场可编程门阵列（FPGA）作为核心控制器件,为CCD提供多路驱动信号。CCD模拟信号经过滤波、放大、采样和AD变换,转换为数字信号输出给数传系统。通过对视频电子学系统进行仿真和实测,在-20℃下,暗电流噪声±0.003mV,信噪比45dB,驱动电路符合设计预期要求。

In order to meet the requirement of low noise detection in low-light remote sensing,a video electronic system of space camera is designed by using the back illuminated frame transfer surface array CCD of British company E2 V.The circuit components of the system are given.Around the main components of noise,the driving and related circuit of the back illuminated array for low-light imaging system are designed to obtain a good signal.It effectively inhibits the dark current noise and video circuit noise of CCD.The imaging system using Xilinx＇s Virtex-II field programmable gate array（FPGA）as the core control device to provide a variety of driving signals for CCD.CCD analog signals are converted to digital signals after filtering,amplification,sampling and AD transformation,and finally put it out to the digital transmission system.By simulating and measuring the video electronics system,the dark current noise is ±0.003 mV at-20℃and the signal-to-noise ratio is 45 dB.The driving circuit meets the expected design requirements.