Efficient Spectral Techniques for Sequential ATPG

We present a new test generation procedure for sequential circuits using spectral techniques. Iterations of filtering via compaction and spectral analysis of the filtered test set are performed for each primary input, extracting inherent spectral information embedded within the test sequence. This information, when viewed in the frequency domain, reveals the characteristics of the input spectrum. These spectral characteristics are then used to generate future vectors. We develop a fault-dropping technique to speed up the process. We show that very high fault coverages and small vector sets are consistently obtained in short execution times for sequential benchmark circuits.