The manufacturing of high-quality and reliable semiconductor memories is very important. Many memory testing algorithms have been proposed to improve the quality of semiconductor memories by screening out different me...
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The manufacturing of high-quality and reliable semiconductor memories is very important. Many memory testing algorithms have been proposed to improve the quality of semiconductor memories by screening out different memory functional faults. However, the relationships between memory function fault types and the types of defects which cause the functional faults are not well understood. Therefore, the effectiveness of memory testing algorithms based on the functional fault models cannot be realistically determined. This paper evaluates the effectiveness of the memory testing algorithms based on the defectcoverage by comparing the defectcoverage of known memory testing algorithms and the functional fault coverage of the same testing algorithms using the same defect statistics. The experimental results show that the differences among the defectcoverage of the 11 memory testing algorithms other than checkerboard and sliding diagonal tests were not significant as previously believed using memory functional fault coverage as the coverage metric.
Analog simulation is much less efficient than digital simulation, so it is essential to reduce the number of potential defects to be simulated when assessing defectcoverage of an analog circuit's test. Simple ran...
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ISBN:
(纸本)9781479947225
Analog simulation is much less efficient than digital simulation, so it is essential to reduce the number of potential defects to be simulated when assessing defectcoverage of an analog circuit's test. Simple random sampling (SRS) is a published technique for digital fault sampling;stratified sampling is an improvement explored for analog fault simulation. This paper compares the defect coverage estimation accuracy of several sampling techniques and our improvements based on defect-likelihood-weighted selection, as measured by confidence interval. For practical cases, it is shown that the estimation accuracy of SRS gets progressively worse as defects become less uniform in likelihood, but with weighted selection, accuracy improves. We conclude that defectcoverage can always be estimated sufficiently accurately by simulating fewer than a thousand defects (and usually much fewer), regardless of circuit size, analog/digital content, and defect likelihood distribution.
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