DelayFault Testing Tutorial

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Delay-Fault Testing Tutorial

• Acknowledgement This presentation is adapted
  from Professor Janak Patels tutorial on the same
  topic available on the web at http//courses.ece.
  uiuc.edu/ece543/docs/DelayFault_6_per_page.pdf

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Outline

• Common Fault Models (Review)
• Defects and Delay Faults
• Delay Fault Models
• Transition Faults
• Path Delay Faults
• Robust Path Test
• Non-robust Path Test

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Common Fault Models
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Only if no other path delay is increased.
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Exercise

• Consider the 4-Nand implementation of the XOR
  gate in the previous slide. There are six I/O
  paths hence 12 path delay faults. For each of
  these faults, determine if it is robustly
  testable, only non-robustly testable or not
  testable (functionally redundant). Provide
  justification for your answers.

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Broadside is also called launch-off-capture
test. Skewed-Load is also called launch-off-shift
test.
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Timing for launch-off-capture Transition-delay
fault testing
IC Initialization Clock LC Launch Clock CC
Capture Clock SEN Scan Enable
This figure is borrowed from the paper, Ahmed et
al., ITC-2005, Paper 11.1
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Timing for launch-off-shift Transition-delay
fault testing
IC Initialization Clock LC Launch Clock CC
Capture Clock SEN Scan Enable
This figure is borrowed from the paper, Ahmed et
al., ITC-2005, Paper 11.1
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(See Prof. Patels website for details on Segment
Test)
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