The Study And Implement Of Circuit Fault Diagnosis Based On IEEE1445

Trend of the Current diagnostic technology is Standardization. IEEE1445, a crucial criterion in the domain of Digital Test technology, is a important international standard for digital test .it ,IEEE1445,provides a universal format of test import code for the numerous test equipment manufacturers Conform to the standard, the scope of and lifecycle of automatic test equipment will be prolonged.During the period of employing IEEE1445 to resolve the problem of fault diagnose, the test vector set's reduction is a hard problem to the entire developing process . After studying the Rough sets theory in-depth, a reduction algorithms inferred from discernibility matrix and discernibility function which can be likely to reduce the dimension of the test vector sets is putted forward here .on the premise of maintaining the ratio of fault coverage, the experiment result indicates that the algorithm could compress the test vector sets effectively.A total of 39 data files, each of which has distinct specifically format criterion, is involved in the standard of IEEE 1445.The detailed information ,which includes all kings of stimulus ,the names of input and output pins and the corresponding pattern for circuit diagnose, is described in these files. All these files are organized into four functional groups .They are UUT model group ,stimulus and response group,fault dictionary group and probe group. Different test methods, end to end fault Dictionary and probe based on the standard ,are described detailed here. Diagnostic mechanism of three kind of test methods is discussed embedded in this thesis The material realization flows based on different test methods are particular described in manner of chart .In addition., based on the "Platform for Developing Fault Diagnosis System of Circuit Board", the Diagnosis module for Circuit Board based on the standard of IEEE1445 utilizing the COM technology is realized in this paper. The module is integrated into the platform for developing fault diagnosis systems of circuit boards A example that applying the Diagnosis module to accomplish some particular diagnose mission is introduced in the paper. The diagnosis result shows that the Diagnosis module, which could finish the actual diagnose mission efficient, would take on practicality signification.