Publication
As-Robust-As-Possible Test Generation in the Presence of Small Delay Defects using Pseudo-Boolean Optimization
Stephan Eggersglüß; Rolf Drechsler
In: Proceedings of DATE 11 - Design, Automation & Test in Europe. The European Event for Electronic System Design & Test. Design, Automation & Test in Europe (DATE-11), March 14-18, Grenoble, France, 2011.
Abstract
Delay testing is performed to guarantee that a manufactured
chip is free of delay defects and meets its performance
specification. However, only few delay faults are robustly testable.
For robustly untestable faults, non-robust tests which are of
lesser quality are typically generated. Due to significantly relaxed
conditions, there is a large quality gap between non-robust and
robust tests. This paper presents a test generation procedure
for As-Robust-As-Possible (ARAP) tests to increase the overall
quality of the test set. Instead of generating a non-robust test for
a robustly untestable fault, an ARAP test is generated which maximizes
the number of satisfiable conditions required for robust
test generation by pseudo-Boolean optimization. Additionally, the
problem formulation is extended to incorporate the increased
significance of small delay defects. By this, the likeliness that
small delay defects invalidate the test is reduced. Experimental
results on large industrial circuits confirm the quality gap and
show that the generated ARAP tests satisfy a large percentage of
all robustness conditions on average which signifies a very high
quality.