机载计算机BIT设计技术及策略研究

On Implementing and Researching BIT Capability in Airborne Computer

机内测试(Built-in Test,BIT)技术是改善系统或设备测试性和维修性的重要途径,通过在机载计算机中设计专门的BIT算法,可以达到大幅度提高机载计算机的可靠性和安全性的目的,但高的虚警率是阻碍其广泛应用的一个重要原因;在对机载计算机BIT虚警原因进行分析的基础上,提出一种新型的机载计算机BIT设计策略,并给出了算法流程图;提出了数字I/0通道、A/D、D/A通道、串行接口等关键部分的故障检测解决方案,经过实践证明该策略的测试覆盖率达90%以上,降低虚警率约35%,明显提高了机载计算机的可靠性及可维护性。

BIT （Built--in Test） is an important ways to improve the testing and maintenance performance of a system or equipment. The special BIT arithmetic in the airborn computer can increase the reliability and security of airborn computer obviously. But the BIT technolo- gy＇ s widely use is hindered by the high false alarm rate. A new BIT design strategy and arithmetic in airborn computer for reducing the false alarm rate is proposed in this paper. And some key technologies＇ solutions is given in this paper, such as digital I/O channels, A/D chan- nels, D/A channels and serial interface. It is proved by practice that the BIT design strategy proposed in this paper can improve the test cover rate about to 90%, reduced the false alarm rate to 35% , increasing the reliability and maintainability of the airborn computer.