摘要
介绍北京同步辐射装置(BSRF)真空紫外(VUV)站针对圆二色谱信号处理要求,设计实现硬件信号处理部分。该部分包括预放大、3阶Bessel低通滤波、交直流分离、交流二次放大和6阶Chebyshev带通滤波器等,采用AD620仪放和MAX274滤波芯片为主要器件,对探测器经前置放大器输出的mV级直流、μV级交流圆二色信号进行硬件处理。该设计在实验站,以商用信号处理仪器SCU-90为对比,以CSA标准品为对象进行测试。实验结果表明,与SCU-90相比,该设计处理得到圆二色信号峰值位置为标准值290nm,二者没有偏差,且光谱波形平滑,证明该设计很好地实现了交直流信号分离放大和滤波功能。同时,该设计背景噪声比SCU-90更低,在信噪比方面有一定改善,从而在小信号探测方面更具优势。
A Circular Dichroism （CD） signal processing device is designed which aims at the demand of CD signal processing in 4B8 VUV station,Beijing Synchrotron Radiation Facility （BSRF）. The device mainly includes the pre - amplify part,3 ranks Bessel low pass filter,divider of DC/AC signal, AC signal amplifier and 6 ranks Chehyshev band pass filter. In the device,instrumentation amplifier AD620 and continuous - time active filter MAX274 are adopted as main chips. Now, in BSRF VUV station,the device has been tested with standard CSA sample and result has been compared to that obtained by SCU- 90,which is commercial signal processing equipment. The experiment result shows that the wavelength of CD signal peak obtain by our designed device is the standard 290nm and is same to that obtained by SCU -90, and the CD spectrum gotten by the device is very smooth. It is proved that the device has achieved the designed aims. At the same time, it can be seen that the background noise of our designed device is lower than that of SCU- 90,and the device has more advantages than SCU- 90 in CD small signal detection.
出处
《现代电子技术》
2010年第4期1-4,共4页
Modern Electronics Technique
基金
国家自然科学基金资助项目(10635060
20871116)
中国科学院高能物理研究所创新基金项目
中国科学院高能物理研究所青年创新基金项目
