Research On The Key Technologies Of Stacked Micro Data Acquisition System

Currently,new type of data acquisition system is developing towards the direction of miniaturization,function generalization and channel expansion.The stacked micro data acquisition system is designed based on the miniature structure,which possesses the characteristics of flexible configuration and easy expansion.It can collect and store the information of vibration,shock,pressure,strain and temperature in the working process,and has important practical significance in the field of vehicle safety testing,aerospace test analysis,safety equipment research and development.According to the requirement in the design of the stacked micro data acquisition system,the hardware circuit and the FPGA control logic of the acquisition system are introduced in detail in this paper.The main work has done in several areas below:(1)Firstly,the bridge sensor interface circuit,the front-end programmable amplifier and filter circuit are designed in system,so signal conditioning settings can be set according to the programmed parameters.Secondly,the synchronous acquisition circuit is designed for 3 independent AD converter,and the asynchronous FIFO is used as buffer memory to collect the data of each channel.(2)Considering the design requirements that acquisition system can be flexibly configured the number of acquisition module and acquisition channels be extended,starting from the point of view that optimization of the physical interface and reliable communication,a multi-point interconnect bus communication link is designed based on the M-LVDS interface.This paper analyzes and explains the multi point communication technology of M-LVDS,and provides instruction and data transfer frame format between data acquisition module and control module.(3)This system has written the logic program of each control module with VerilogHDL,And the function simulation and timing analysis of each module are carried out by Modelsim software.Finally,the system test platform is set up,completing the debugging of logic programs with Chip Scope software,testing and analysising of the conditioning circuit with related instruments,and the instruction and data transmission performance of the system are verified through PC software.The test results show that the function of this system works well.The gain coefficient,filter parameters and sampling rate of each channel can be set up by the computer software,the number of collection modules can be configured flexibly,and the acquisition channel can be extended according to the needs of users.The data transmission between the acquisition module and the control module is stable,and the bandwidth meets the requirements,The overall performance of the system is good,which has value of Engineering application.