Efficient identification of (critical) testable path delay faults using decision diagrams

We present a novel framework to identify all the testable and untestable path delay faults (PDFs) in a circuit. The method uses a combination of decision diagrams for manipulating PDFs as well as Boolean functions. The approach benefits from processing partial paths or fanout-free segments in the circuit rather than the entire path. The methodology is modified to identify all testable critical PDFs under the bounded delay fault model. The effectiveness of the proposed framework is demonstrated experimentally. It is observed that the methodology outperforms any existing method for identifying testable PDFs. Its scalability by focusing on critical PDFs is demonstrated by experimenting on very path-intensive benchmarks.