2.1 - A Successful Effort in Improving the Efficiency of Weighted
      Random Pattern Test System

Authors: Paul Chang, Brion Keller, David Pruden
Univ/Comp: IBM
Presenter: Paul Chang - changhp@us.ibm.com

******** Abstract:
Weight Random Pattern tests (WRPT) are being heavily used for
large chip designs due to the benefit of using significantly less
tester memory compared to Stored Pattern tests. But the inherent
nature of WRPT requires more test cycles be applied to the product
in order to achieve equivalent fault coverage.
Thus, it is critical that WRPT tests be as efficient as possible in
order to minimize the cost of their application.
This paper describes ways to improve the efficiency of current WRPT
through the use of reverse weight simulation, two-pass weight development,
test sequence enhancement, and system parameter default optimization.
The results show that significant reduction in tester cycles are achieved.
This translates into considerable savings for manufacturing due to the
reduction in test time.