Mixed symbolic-numerical techniques in fault diagnosis using fault rubber stamps

Fault diagnosis is very important for the development and maintenance of safe and reliable electronic circuits and systems. Many fault diagnosis methods were developed during the past years but the tolerance effect as well as the limited testability for large analog circuits still exist and are difficult to deal with. A symbolic fault diagnosis method for analog circuits is proposed in this paper based on rubber stamps. A method to limit the number of detectable faults in low-testability circuits is also advised based on the ratio of nominal power dissipation of each element to its power rating which is assumed to have good correlation with the element probability of failure.