Research And Realization Of In-Circuit Test Based On VI Curve

With the development of the modern electrical technique, the circuit test is also developing. The main work of this thesis is about the research and realization of the In-Circuit Test which is based on the method of the VI curve test.Firstly the origin and theory of VI curve test is described. Then the effect of frequency in the VI curve test is discussed. Based on it, the thesis puts up the main parameters about the In-Circuit Test and the ways of the selection. The following chapter tells the external test of VI curve test, the skills in VI curve test, the position of VI curve test in the troubleshooting and so on .Automatic fault diagnosis and circuit identification using analog signature analysis are of great practical interest. The problem of automatic comparison of nearly similar analog signatures is addressed later. Two known correlation-based similarity criteria are compared, and a new criterion is introduced by the use of a weighting factor, which improves the discrimination capability. Comparative results for various signatures are given, and useful applications of this work are discussed. In the end, software of VI curve test is developed after utilizing compositive hardware resource, which can be able to test diagnosis board in circuit and detect the fault units rapidly on the board.