Design Of Digital MCA Base On FPGA And STM32Technology

Nuclear spectrum measurement technology plays an increasingly important role in high-energy physics, nuclear physics and nuclear technology as an important information access means. Especially in recent years, with the deterioration of the global environment, disaster of earthquake landslides frequently, nuclear crisis and a serial of problems harm to human survival and living. Nuclear technology measurement is particularly important.Multi-channel pulse amplitude analyzer offers a strong support for energy spectrum quantity as an important part of X ray fluorescence analysis. The nuclear pulse signal of nuclear radiation detector output is being digital quantified and then through the special analysis and treatment. We can easily obtain the spectral information of ray. So Multi-channel pulse amplitude analyzer plays a vital role in mineral prospecting and exploration, medical care, environment monitoring and so on.With the rapid development of computer technology, digital electronic technology in recent years, the traditional analog multi-channel pulse analyzer has been replaced by the digital multi-channel pulse amplitude analyzer gradually. The digital multi-channel pulse amplitude analyzer has great advantages in terms of cost, volume, power consumption, measurement accuracy and speed respect to the analog multi-channel pulse analyzer.In this article, the design of digital multi-channel pulse amplitude analyzer is based on Altera company’s Cyclone III serial FPGA EP3C5E144and STM32F103VET,which based on ARM Cortex-M3kernel and made by ST. The external high-speed A/D converter used AD9235.AD sampling control module, peak extraction module, dual port RAM design and control module, real pulse FIFO store module and SPI read and write control module achieved by verilog HDL in FPGA.STM32used SPI to transmit the data and command response and then communication with the host computer with USB virtual serial port as a bridge. The computer test software is written by Visual Studio2005using C#language, at the same time using ZedGraph which is a open-source drawing control part to curve the spectral and pulse data. It is convenient and fast to curve with the help of it.Finally, in order to test the accuracy and reliability of the system, a large number of simulations are conducted, after the system is correct and stable, then measured the simulation signal in laboratory and the55Fe real nuclear pulse signal from the XR-100SDD semiconductor detector,at last the measurement approved the system achieve the desired goal.