2012 IEEE 21st Asian Test Symposium (2012)
Niigata, Japan Japan
Nov. 19, 2012 to Nov. 22, 2012
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/ATS.2012.78
In recent years, a number of high level applications have been reported to be tolerant to errors resulting from a sizable fraction of all single stuck-at faults in hardware. Production testing of devices targeted towards such applications calls for a test vector set that is tailored to maximize the coverage of faults that lead to functionally malignant errors while minimizing the coverage of faults that produce functionally benign errors. Given a partitioning of the fault set as benign and malignant, and a complete test vector set that covers all faults, in this paper, we formulate an integer linear programming (ILP) problem to find an optimal test vector set that ensures 100% coverage of malignant faults and minimizes coverage of benign faults.We also propose a test strategy based on selectively masking appropriate outputs of the circuit to partition the circuits at production test into three bins - malignant, benign, and fault-free. As a case study, we demonstrate the proposed ILP based test optimization and functional binning on three adder circuits: 16-bit ripple carry adder, 16-bit carry lookahead adder, and 16-bit carry select adder. We find that the proposed ILP based optimization gives a reduction of about 90% in fault coverage of benign faults while ensuring 100% coverage of malignant faults. This typically translates to an (early manufacturing) yield improvement of over 20% over what would have been the yield if both malignant and benign faults are targeted without distinction by the test vectorset.
Circuit faults, Cancer, Vectors, Adders, Optimization, Manufacturing, Delay
S. Sindia and V. D. Agrawal, "Tailoring Tests for Functional Binning of Integrated Circuits," 2012 IEEE 21st Asian Test Symposium(ATS), Niigata, Japan Japan, 2012, pp. 95-100.