The Design Of High Speed Multi-channel Pulse Amplitude Analyzer Based On TMS320F2812

Nuclear analytical techniques are an important part of modern nuclear science and technology, nuclear analytical techniques have numerous irreplaceable features that conventional non-nuclear technology doesn’t have, such as high sensitivity, high accuracy and precision, high-resolution(including spatial and energy resolution), non-destructive, multi-element determination of capacity and specificity, which provides a reliable basis for the further development of natural sciences. The nuclear analysis techniques based on energy spectrum analysis are widely employed in the field of medicine, geology, energy, archeology and industrial online analysis, as a core component of energy spectrum acquisition system, the multi-channel pulse amplitude analyzer has important value of application.This paper designed a practical, high-speed, multi-functional multi-channel pulse amplitude analyzer based on the high-performance DSP TMS320F2812 produced by TI Corporation. Taking advantage of dual memory switching to separate the data acquisition storage and data transfer storage, the multi-channel pulse amplitude analyzer achieves high-speed data transmission with PC via the USB2.0 interface, which makes it achieve time-shared energy spectrum. The idea of dual memory switching and high-speed data interface makes energy spectrum acquire, data upload and display simultaneously and ensures uninterrupted time spectrum data; the energy spectrum measured and saved in time subsection provides basic data for analyzing the amount of the same energy rays. In addition, this design integrated pulse time-shared counting function, which not only realizes the energy spectrum acquisition function, but also provides the temporal distribution of nuclear event incidence.This design makes full use of the hardware resource integrated in TMS320F2812 that increases the integration of the system. The USB2.0 interface is based on FT2232 H chip of FTDI Corporation that can be configured as a virtual serial port using the USB firmware and VCP(Virtual Serial Port) driver provided by FTDI Corporation, which makes the USB interface can be operated just like standard serial port, simply and expediently, the design solution reduces system cost while the success rate of design is ensured.Energy spectrum display software based on windows operation system is designed using VS2010, the multi-channel pulse amplitude analyzer achieves function selection, sampling time settings, spectrum display and storage under the control of the energy spectrum display software. The multi-channel pulse amplitude analyzer we designed can operate in three modes—energy spectrum measuring, pulse counting, energy spectrum measuring and pulse counting at the same time. The experiment shows the multi-channel pulse amplitude analyzer is able to collect and store time-shared energy spectrum data and pulse counting every 30 ms. In the energy spectrum measurement mode, the spectrum counting rate up to 560kcps; in the pulse counting mode, pulse counting rate up to 1.9mcps; in the energy spectrum measurement while pulse counting mode, the spectrum counting rate up to 300 kcps and pulse counting rate up to 0.9mcps. The multi-channel pulse amplitude analyzer has high counting rate and resolution in all three modes, which is stable and reliable for operation and able to satisfy the requirements of elemental analysis work.