Scenario-based set-level HTOL test (ASH III) for product quality and reliability qualifications on high-speed APs

In a succession of the set level stress test for high speed mobile application processor (AP) reliability [1], At-Speed HTOL (ASH) incorporated by user conditions was employed to realistically project the field failure rate of product. Using the worst case-scenario test with different frequency and operation duty, the failure modes veiled behind the conventional HTOL can be surfaced and then reconciled, which is further evolved as a failure screening technique during volume production. In addition, the simulation methodology to determine product Vmin-guardband (GB) in pre-silicon phase is also developed and compared to the Product Vmin-GB results. The results of ASH with scenario test can extend our understanding of an effective methodology to ensure robust design from design for test (DFT) and to achieve decent field failure target.