- Author: Kuan-Yu Liao, Chia-Yuan Chang, and James Chien-Mo Li, National Taiwan University - Publication: IEEE Transaction on Computer-Aided Design of Integrated Circuits and Systems, 2011

1. National Taiwan UniversityNational Taiwan University
A Parallel Test Pattern
Generation Algorithm to Meet
Multiple Quality Objectives
K.Y. Liao, IEEE Trans. Comput.-Aided Design
Intergr. Circuits Syst., Vol. 30, Issue 11
1
J.Y. Chen, 2015/09/15

2. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
2

3. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
3

4. Outline
• Introduction
– Background knowledge
– PODEM Quick Review
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
4

5. Introduction -­ Background Knowledge
• Single stuck-­at fault (SSF) model is no longer
effective enough in deep sub-­micron (DSM)
circuits
• Several quality metrics are introduced to grade
patterns
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6. Introduction -­ Background Knowledge
• Quality metrics
– N-­detect
– Physical-­aware N-­detect (PAN)
– Gate exhaustive (GE)
– Bridging coverage Estimate (BCE)
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7. Introduction -­ Background Knowledge
• To achieve high quality test pattern generation (TPG),
quality objective are introduced during the process
• Additional quality objectives may cause lots of
backtracks during TPG
• Some tries to grade and select patterns from large-­N-­
detect test set generated by traditional TPG tool
• SWK adopted bit-­wise parallel strategy to realize search-­
space parallelism, thus get more chance to justify
additional quality objectives
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8. Introduction -­ PODEM Quick Review
• Path-­sensitizing ATPG algorithm
• After fault activation, system choose a gate from
D-­frontier and then gradually map corresponding
D-­drive objective to a PI/PPI decision, called
backtrace
• After each decision make, run implication to
update the logic value of circuit
• Heuristics such as X-­path search are adopted
for early avoidance of backtrack
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9. Outline
• Introduction
– Background knowledge
– PODEM Quick Review
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
9

10. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
10

11. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
11

12. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
– 7-­Valued Logic
– System Flow
• Experiment Result
• Conclusion
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13. SWK -­ 7-­Valued Logic
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14. SWK -­ 7-­Valued Logic
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15. SWK -­ System Flow
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16. SWK -­ System Flow
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17. SWK -­ System Flow
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18. SWK -­ System Flow
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19. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
– 7-­Valued Logic
– System Flow
• Experiment Result
• Conclusion
19

20. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
20

21. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
21

22. Experiment Result
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23. Experiment Result
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24. Outline
• Introduction
• Split-­into-­W-­Clones(SWK)
• Experiment Result
• Conclusion
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25. Conclusion
• SWK optimize test pattern quality during TPG
• Might able to integrate SWK into other
parallelism strategy
• Word size are predefined and less flexible
• Only support parallel pattern generation target
on single fault
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