Multi-channel High-precision A/D Acquisition Card Design Based On FPGA

Data acquisition is an important part in the signal and information system and it alsois the key link in the digital signal processing. Data acquisition is a process that makes thesensor output signal converted to digital signal can be recognised by computer. Theconverted digital signal is calculated and processed by the computer according to thedifferent needs.The traditional method of high-speed data acquisition system design is to use singlechip microcomputer and hardware FIFO, but the control is single, and not easy to upgradefor this kind of system. To the FPGA circuit logic, its relationship is clear, chip delay issmall, fast, and its internal logic circuit can be described by the VHDL or VerilogHDL,and it is easy to modify and upgrade. If the FPGA controller is used in high-speed dataacquisition system will greatly improve system stability and reliability.This paper designed a multi-channel, high-precision, high-speed data acquisition cardbased on FPGA(Field Programmable Gate Array abbreviation). It is mainly consists ofFPGA control module, the data acquisition module and interface bus, and it has theadvantages of high speed, low power consumption and fast data transfer rate. The dataacquisition card uses ADS1246to finish signal amplification and analog to digitalconversion, then uses FPGA clock system and internal control module to realize datacache and data transformation, and finally transfers the data stored in FPGA to thecomputer by the serial interface.As the control center and transmission bridge, FPGA played a very important part inthis system and the sequential control module of the system can be achieved by the VHDL.Utilizing FPGA not only accomplishes the whole digital circuit and also highly improvesthe adapt ability and flexiblility of the system.This paper based on the memory of the data acquisition, mainly studies theanalog-digital conversion, FPGA design and serial interface design, completed the circuithardware design and software design, and verified the feasibility of the system through thesystem simulation...