考虑声光可调谐滤波(AOTF)成像光谱仪的需求,设计了它的CCD成像电子学系统。选用e2v公司的CCD芯片CCD57-10作为图像传感器,提出了DC/DC+LDO的架构实现各偏置电压;基于现场可编程门阵列(FPGA)等器件产生驱动时钟,AD9826完成CCD输出模拟信号到数字信号的转换,并通过USB及CameraLink接口与计算机通信。设计了CCD保护电路,并优化了数模混合电路的印刷电路板(PCB)布局结构。对各功能单元的实际测试表明:各偏置电压纹波噪声峰峰值小于10mV;AD转换精度达12bit;系统能够正确成像,图像传输速率可达10frame/s,图像信噪比优于54dB,系统总功耗不足5W。设计结果满足AOTF成像光谱仪对CCD成像电子学系统的要求。
In consideration of the requirement of Acousto Optics Tunable Filter(AOTF) imagers,a CCD imaging electronic system was designed.The CCD chip CCD57-10 from e2v company was chosen as the image sensor,and the DC/DC+LDO structure was advanced to generate each bias voltage.Then a Field Programmable Gate Array(FPGA)was used to generate driving clock,the AD9826 was taken to convert the CCD output analog signal to a digital signal,and USB or CameraLink interface was adopted to communicate with a computer.Furthermore,a CCD protect circuit was designed and the layout of Printed Circuit Board(PCB) of mixed signals was optimized.The test results for functional units indicate that the system can offer the peak to peak ripple noise of bias voltage less than 10 mV and a AD convert precision of 12 bit.Moreover,the system can image correctly with a image transmit rate of 10 framd/s and the signal to noise ratio better than 54 dB.The system power consumption is less than 5 W.The design can meet the demands of AOTF imaging spectrometers for CCD imaging electronic systems.