A new test points selection method for analog fault dictionary techniques

Abstract

A new efficient method to select an optimum or near optimum set of test points for fault dictionary techniques in analog fault diagnosis is proposed. This is done by constructing a fault-isolated table firstly according to the integer-coded fault dictionary, and picking the special test points with particular fault isolate abilities out from the candidate test points set. This step can help us save the total cost of computation and even find the global minimum test-point set directly. After this step, the selected test points might isolate most of the defined faults together, and these isolated faults (rows) and the chosen test points (columns) are deleted from the fault dictionary, the dimension of which will reduce quite a lot. And then the inclusive and exclusive approach are combined together to choose other optimum test points from the candidate test points set to solve the problem. Three analog circuits' examples and the statistical experiments are given to demonstrate the feasibility and effectiveness of the proposed algorithm, the existing classical algorithms are also used to do the comparison. The results indicate that the proposed method has a better tradeoff between the solution accuracy and the computational cost, and it is superior to other methods in its computational efficiency and quality of final solution. Therefore, it is a good solution to minimize the size of the test-point set, and practical for medium and large scale systems.