Design And Implementation Of Low-power USB Multi-function Data Acquisition Based On FPGA

As the scenes of data acquisition applications become more and more wide,and the types of signals to be measured become more and more diverse,so a single type of data acquisition system can no longer meet the actual needs.In addition,most acquisition systems eventually have to reconstruct dynamic analog or digital signals,so data feedback output is just as important as data acquisition.However,the current common interface of the acquisition system in industrial control is PCI or CPCI,not inconvenient for personal computers.Therefore,in order to meet the diversity of data collection,this paper designs and implements a USB multi-function data acquisition system to make the data acquisition system penetrate into more application scenarios.The low-power data acquisition system designed by this paper communicates with the host computer through USB2.0 and it is powered by the USB bus because it consumes only 1.5 W.The specific functions and indicators of this system are as follows:A 16-bit precision ADC can support 16 single-ended(or 8 differential)analog signal input channels,and each channel can be independently configured with ±0.2V?±10V multiple input ranges.The Signal to noise ratio is as high as 88.2dB,and the single channel has a maximum rate of 500 kS/s.A 16-bit precision DAC can realize two channels of analog signal output ± 10V voltage and offset adjustment;there are 16 digital input and output channels that can be configured for various functions such as timers,counters,and frequency generators.For the convenience of user,this paper also designed a PC software,which can configure and control the input and output of analog and digital signals,as well as display and store the acquisition results and data waveforms in real time.The data acquisition system designed in this paper reduces the price,while achieving high performance compared with foreign data acquisition systems such as NI-USB 6212,and can replace foreign products,make up for the shortcomings of the domestic data acquisition system.This paper first introduces the research background and development status of data acquisition systems.Then,the functions,indicators and overall framework of the system are introduced and the three difficulties of circuit design are analyzed and summarized.After that,the system is divided into four functional modules:ADC,DAC,digital 10 and USB.The hardware circuit design,FPGA program design and PC software design of different functional modules are elaborated.Finally,the software and hardware test platform of the system was built,and all the main functions and indicators were tested.The test results show that the whole system can work normally and meet the system function and index requirements.