Design Of Multi-channel Data Acquisition System Based On SOC Single Chip

With the rapid development of science and technology, in areas such as basic scientific research, industrial applications, national defense science and technology, the precision of data acquisition have put forward higher requirements. On the other hand, computer technology, microelectronic technology, communication technology rapid development and widely application, data acquisition system functionality and performance have been significantly improved.The development of high-precision of the Data Acquisition system is restricted by the level of the A/D converter of the chips. The data acquisition system uses C8051F350 microcomputer as a core controller, which has a high-resolutions(24) ofΣ-ΔADC, temperate drift and relatively small imbalance coefficients are in line with the Data Acquisition system requirements. On the basis of theoretical analysis, the paper complete the high-precision and multi-channel system which reaches eight channel for the analog inputs and 24-bit resolution.Data acquisition system consists of lower level computer acquisition module and virtual instrument. lower level computer acquisition module is based in the whole collection system.This paper analyzes a wealth of analog, digital resources of C8051F350, complete the hardware design, including power, signal conditioning, RS-485 network, debugs and store modules, simplifies the complexity of data acquisition circuit, considering anti-disturbance measures, adopt channel segregation, simulated filtering, independent power supply etc measures to improve system performance and achieve the system precision acquisition. The PC software is designed under the LabWindows/CVI, which has good human machine interface and is easy to operate. The PC software can acquire and deal with data automatically and realize the function of saving of real time data, data printing. PC and lower place machine based on self-built communication protocol using RS-485 network communication, realizing collecting data and control parameters on the exchange.Data acquisition preliminary experiment and the analysis of experimental results indicate, the data acquisition system of the technical indicators have reached design goal and long time running performance stability and anti-jamming is good.