Development On The ~3He Tube Readout Electronics System Based On SOPC

Neutron, which has the advantage of no charge and strong penetration, was used to detect and understand the microscopic world. In recent years, neutron powder diffraction spectrometer had been widely applied to detect the scattering neutron in various countries, with the rapid development and the wide application of domestic and foreign neutron technology. In order to obtain the microstructure information and motion state of material, the 3He tube was used to record the location and time of flight neutron; and the time and position information was collected by the readout electronics system. A design of the 3He tube readout electronics system based on FPGA and optical fiber communication was proposed in the background of the project ―General powder diffraction spectrometer 1 inch pipe 3He tube readout electronics equipment development‖.The readout electronics system was designed by researching and analyzing the application of the neutron powder diffraction spectrometer at home and abroad. The system works as follows: the 3He tube was hit by the scattering neutron, and generated weak electrical signals in the ends; then the signal was transmitted into the readout electronics system; last the time and location information of the scattering neutron was provided to the users by analyzing and disposing. High-performance FPGA was used as the data processing control system to deal with the charge and time information, greatly improving the speed of data processing. The optical fiber was used to transmit data, improving the accuracy and transmission speed of the readout electronics system.The completed work of the 3He tube readout electronics system was mainly introduced in the paper. Firstly, the hardware circuit design of data acquisition module, FPGA module, and optical fiber network module was exposed in detail; secondly, the detail design of data acquisition controller was designed and electronics readout SOPC system was built; lastly, the system was tested online in Signal Tap II logic analyzer and Nios II IDE. After testing the system, the design requirement of the real-time data acquisition, data storage and data transmission was realized preliminary.