Optimization of Mutual and Signature Testing Schemes for Highly Concurrent Systems

Signature-based techniques are well known for the Built-in Self-test of integrated systems. We propose a novel test architecture which uses a judicious combination of mutual testing and signature testing to achieve low test area overhead, low aliasing probability and low test application time. The proposed architecture is powerful for testing highly concurrent systems in applications such as iterative logic arrays, real-time systems, systolic arrays, and low-latency pipelines which tend to have a large number of functional modules of a similar nature. The use of mutual testing helps in testing “self-loop” modules which cannot be tested using simple signature-based schemes. We provide graph-theoretic optimization algorithms to optimize the test area and test application time of the resulting test architecture.