K. Chakrabarty et Jp. Hayes, ON THE QUALITY OF ACCUMULATOR-BASED COMPACTION OF TEST RESPONSES, IEEE transactions on computer-aided design of integrated circuits and systems, 16(8), 1997, pp. 916-922
The accumulator-based compaction (APC) technique uses an accumulator t
o generate a composite fault signature for a circuit under test. The e
rror coverage for this method has been previously analyzed using Marko
v chains. We describe an alternative technique for calculating the err
or coverage of ABC using the asymmetric error model. This technique re
lies on the central limit theorem of statistics and can he applied to
other count-based compaction schemes. Our analysis shows that ABC prov
ides very high coverage or asymmetric errors. Experiments on the actua
l fault coverage for the ISCAS 85 benchmark circuits show that extreme
ly high postcompaction fault coverage (close to 100%) is obtained with
ABC. They also indicate that the use of a rotate-carry adder does not
always improve the fault coverage;in some cases, the fault coverage i
s actually reduced.