The Design Of PMT Readout System

The Jiangmen neutrino experiment is another neutrino experiment under construction after the existing Dayawan neutrino experiment.It has more important scientific goals and missions.It is a high-energy physics institute in China and an internationally relevant neutrino research.Institutional cooperation projects.As a neutrino detection experiment,the core detector used is composed of a PMT array,so designing a PMT readout system is indispensable.The PMT readout system,based on project requirements,requires reading and data acquisition of the photoelectron signals generated by the PMT detector.According to the characteristics of single-photon signals and project requirements,it is necessary to design signal readout circuits and write related FPGA firmware programs for data acquisition.The PMT readout system is mainly composed of two modules:a signal readout module and a data acquisition module.According to the requirements of the project,the two major modules are made into a mother board structure and connected through the FMC interface.The signal readout module performs the digital-to-analog conversion processing after reading the optical signal generated by the PMT.The digital-analog converted data is sent to the data acquisition module through the FMC interface.The main function of the data acquisition module is to receive the signal data sent by the readout module,process the received data,and packetize and send the data to the PC.The main functions implemented by the FPGA firmware program are the control of the PMT readout system and the transfer of data.The design data receiving module receives the data sent by the signal reading module.The SPI port protocol is used to configure the ADC,DAC,and PLL chips to control the relevant circuits of the signal readout module.Through the TCP/IP network communication protocol design,data packetization and transmission are realized.The design utilizes the powerful performance of FPGA to design the data acquisition function and communication protocol.Each level of the program includes a caching mechanism to ensure the stability of the data.For the function of the PMT readout system,according to the signal requirements,input the test signal of the corresponding index,and finally restore the signal from the PC through the Lab View tool,thus verifying the readout and acquisition functions of the system.