Design Of Multi-channel Data Acquisition Card In Vacuum Environment

Data acquisition system plays a very important role in space simulator.Aiming at some problems in data acquisition system of space environment simulation equipment at home and abroad,this paper designs a multi-channel standard voltage and current data acquisition card based on FPGA chip through practical verification and optimization.As a subsystem of multi-channel data acquisition system working in vacuum environment,the board system uses EP3C25E144I7 chip of Altera Company,AD7699 chip of ADI Company,ADM5411 isolation chip of ADI Company and other ancillary chips to construct the whole digital circuit system.It realizes many functions such as multi-channel parallel data acquisition,digital filtering,parameter configuration,calibration,host computer communication,power-off saving of key parameters and so on.The main work of this paper includes board schematic design,four-tier PCB design,design and Simulation of FPGA chip based on Verilog-HDL hardware description language,system testing,functional verification,and reliability verification in vacuum environment.The designed board can work for a long time in high vacuum environment.It supports the maximum 24 channels to collect and process current/voltage data at the same time.The sampling rate reaches 500 KSPS,and the data has no jitter.The error is less than 0.5%.The work of this paper verifies that the multi-channel voltage and current acquisition system based on the FPGA chip is suitable for the special requirements of vacuum environment,and has a good reference for the improvement and optimization of space ring mode equipment.