Power-aware Test Scheduling for IEEE 1687 Networks with Multiple Power Domain

Payam Habiby, Sebastian Huhn, Rolf Drechsler

In: 33rd IEEE International Symposium on Defect and Fault Tolerance in VLSI and Nanotechnology Systems (DFT). IEEE International Symposium on Defect and Fault Tolerance in VLSI and Nanotechnology Systems (DFT-2020) October 19-21 Rome Italy 2020.


New test access methodologies are required to cope with the ever-increasing complexity of latest system-on-a-chip designs. The IEEE 1687 standard defines an access methodology to embedded instruments through a reconfigurable scan infrastructure. This technique allows implementing even largenetworks while keeping the individual access time low since onlyrelevant parts of the scan chain are included in the scan path. However, the reconfiguration introduces a timing overhead, which can be mitigated by accessing instruments concurrently. The concurrent activation of instruments forms a critical aspect from the power management perspective since latest designs consist of multiple power domains with individual power constraints. Toavoid any test failures, it must be avoided that the total power consumption of the concurrently activated instruments exceedsthe domain’s power limit. Particularly when considering highly complex IEEE 1687 networks, which reveal the full potential ofthe standard by introducing hierarchical and optimized networks, the power-aware test scheduling is a non-trivial task. This paper proposes a test scheduling scheme for complex IEEE 1687 networks, which heavily orchestrates graph-based methods. In the end, an optimized test plan is determined, which ensures, on the one hand, a minimized overall test access timeand, on the other hand, full compliance with the given powerconstraints. The approach’s efficacy is demonstrated on state-of-the-art benchmark sets involving complex networks with various power domains.

Deutsches Forschungszentrum für Künstliche Intelligenz
German Research Center for Artificial Intelligence