Path Oriented DEcision Making (PODEM)

Automatic-test-pattern generation algorithms generate circuit test patterns, can identify redundant circuit logic and compare various circuit implementations. Functional test is impractical for larger circuits and E-beam testing was very expensive. To overcome the above said difficulties structural test is used. D algorithm was proposed for pattern generation but this algorithm proved to be highly ineffective for faults which needed multiple paths to be sensitized simultaneously. To overcome this inefficiency PODEM was introduced. PODEM expanded the binary decision tree around primary input variables only, thus accelerating the algorithm. PODEM algorithm had a subroutine to check the existence of D-frontier. If not, PODEM backtracks immediately, thus speeding up the process. Backtracing is an important method introduced by Goel in PODEM.