信号调理模块的LXI自动测试系统设计

为满足自动测试系统课程实验的教学演示需要,以某信号调理模块为被测对象设计开发了一套基于LXI总线的多通道自动测试系统;该自动测试系统主要由激励信号源、信号调理模块、数据采集器以及设计的通道选择模块组成;设计的通道选择模块以ATmega328-PU单片机为核心,采用电平转换芯片CH340T实现与上位机间的通信,并且使用ULN2803驱动芯片实现对继电器开关的驱动控制;在软件设计中,使用“生产者—消费者”的架构进行控制软件的设计,采用面向对象的编程思想封装设备的操作函数,根据技术要求基于LabVIEW完成人机交互界面的开发;经实验测试表明,该自动测试系统可由计算机控制产生输入信号调理模块的激励信号,并具备对信号调理模块输出信号的采集、分析处理以及显示功能,同时可以进行测试通道选择切换,在实际应用中满足自动测试系统课程实验的教学演示需求.

Design of the Auto-Test System of Signal Conditioning Module

In order to meet the teaching demonstration needs of the automatic test system course experiment, a set of multi-channel automatic test system based on LAN-based extensions for Instrumentation(LXI) bus was designed and developed with a signal conditioning module as the object under test. The automatic test system is mainly composed of excitation signal source, signal conditioning module, data collector and designed channel selection module. The designed adapter board is based on the ATmega328-PU single-chip microcomputer, adopts the level conversion chip CH340T to implement the communication with the upper computer, and uses the ULN2803 driver chip to implement the drive control of the relay switch; In the software design, the "producer-consumer" architecture is used to design the control software, the object-oriented programming idea is adopted to encapsulate the operation function of the equipment, and the human-computer interface is developed based on LabVIEW according to the technical requirements. Through the experimental test, the automatic test system can be controlled by a computer to generate the excitation signal of the signal conditioning module, and has the functions of collecting, analyzing, processing and displaying the output signal of the signal conditioning module, which meets the teaching demonstration needs of the automatic test system course experiment through practical application.