Research On Data Acquisition System Of Multi-channel Ionization Chamber Based On PCIe Bus

Multi-channel ionization chamber is widely used in heavy ion accelerator to measurebeam profile and beam intensity. Two kinds of multi-channel ionization chamber aredesigned in IMP, one is for the beam transfer line, the other is for the experimental terminal.Because output signals of the detector are very weak it should be amplified by a highsensitivity front-end electronics and be acquired by a high performance, multichannel,simultaneous-sampling data acquisition systems.In the dissertation, a high frequency DAQ system based on PCIe protocol has beendesigned for multi-channel ionization chambers in IMP. A high speed ADC chip is selectedfor acquiring the data from the front-end electronic borad, which is transferred by PCIe busafter buffering and processing by Xilinx’ Virtex-5chip. Except for the hardware, a driverand a teset application have been programmed in this system. Four Analog-to-digitalconversion channels have been designed at80MHz sample frequency BMD/PIO matchesPCI-E x8planes interface, which is generated by Xilinx IP CORE Generator. In order toimprove the development efficiency, Smatac company’s jacks are used to connect aanalog-to-digital conversion board and a FPGA card. Details are described, such as theclock circuit, the configuration circuit, the operating principle of BMD/PIO, theasynchronous FIFO.The test result shows that this system works well at80MHz sample frequency and thetransfer speed of PCIe bus is about570MB/s. The ADC’s performance meets the designrequirements such as DNL, SNR, ENOB.