Design Of Vxibus 4-Channel High Speed Data Acquisition Module

The appearance of VXIbus which is used in Automatic Test System and modular instrumentation indicates that test and instrumentation system has come into a brand-new era. VXIbus data acquisition module plays an important role in many Automatic Test Systems. The characteristics of the input analog signals in the time and frequency domain can be obtained with the acquisition of the module. The hardware and software design of a VXIbus 4-channel high speed data acquisition module is discussed in this thesis, which takes advantage of the VXIbus, data acquisition, FPGA and DSP technologies.After the particular demand analysis, the whole scheme of the automatic test system is introduced. The module is composed of the VXIbus interface, data acquisition and storage circuit, analog conditioning circuit and trigger control circuit. Measurements such as period, frequency, voltage, pulse width are supported by the acquisition and storage of the input signals.In the hardware design, the analog circuit, high-speed A/D convertor, storage control logic and VXIbus interface are discussed. The results of the simulation and analysis of the circuits are given.In the software design, the driver and soft panel of the module conforming to the VPP specification are developed by the LabWindows/CVI. And the developing techniques are also introduced. The design environment of DSP software is also introduced.Finally, the errors generated by each part of the module are analyzed. And the whole error of the module is given. A scheme is proposed to improve the precision performance.