Complex Field Fault Modeling Based Testing Selection Method Of Analog Circuit

There are many problems to be resolved and analysed of analog circuit fault system, assessing the testability metrics and Complexity of the test of a given system is one such problem. In complex electronic circuits, testability features become essential during the design and operational phases of the systems. Currently most of the preferred testing methods are used to choose adequate test frequencies and test points selection, which study the testability of analog circuits in the frequency domain. But the existing fault modeling have obvious deficiencies, such as only suitable for soft faults or hard faults, and which has most can only be used for linear circuits. Therefore, we propose a preferred testing method based the complex fault modeling which can achieve the testability analysis and fault diagnosis of analog circuits. The main research results are as follows:1. The testability modeling is studied for analog circuits based on the complex fault modeling. Compared to the previous fault modeling methods, this method can be used for linear or nonlinear circuit. At the same time, this fault modeling method characterizes soft faults and hard faults as a fault element. The basic idea is to build a relationship between the real and imaginary part of the output voltage which respect to the faulty components, they can build a circle model, i.e. ?,? 0x or ojf U U ?. And this relationship can be used as fault signature and has nothing to do with the value of the faulty component. This relationship can be available through analytical or simulated method available. This fault modeling method which can model the continuous parameter shifting(CPS) faults is proposed in this paper.2. A constraint optimal method to choose the optimal frequencies and test points selection which can achieve the preferred testing of analog circuits. Without transfer function and extensive simulation requirement, this method can model much more fault situations with less test points. The model is derived from the binary quadratic function. In the complex field, the two fault signatures may have two intersections: the fault-free point and the aliasing problem(i.e. fault pair involved(xi, xk)). We can use the sensitive frequency method to solve this problem, which through change the frequency of input signal. Because the sensitive frequency is rely on the fault modeling, which is used to be tested and fault diagnosis. Currently most of the frequency generation methods just using in the hard or DPS faults. In this paper we propose a fault modeling method which can characterizes soft faults(CPS) and hard faults. By using this method, we propose a method which is the test frequency and compaction method is used to selection optimal frequencies in analog circuit. Similarly, the ambiguous set can be determined by the complex field model. By using the integer-coded fault-wise table method to obtain fault dictionary, then use a method to optimum test point selection for fault diagnosis.3. The software system with complex fault modeling and frequency generation and frequency compaction for analog circuit systems is designed and implemented. By using Matlab, the complex fault modeling, frequency generation, frequency compaction, test point selection and generate dependency matrix for analog circuit systems can be analyzed by this analysis system.