Use these drills after completing all topics in Scan Fundamentals. Answer with metric, mechanism, evidence, owner, and regression plan.
[INT][DFT][SCAN-FUNDAMENTALS]
Q: Why does chain balance matter beyond tester time?
A:
Unbalanced chains increase shift time and often create route detours and hold-fix overhead.
FOLLOW-UP TRAP: Treating chain balance as only an ATE problem.[INT][DFT][SCAN-FUNDAMENTALS]
Q: What is the first check when scan coverage unexpectedly drops?
A:
Verify scan replacement legality and non-scan element list before tuning ATPG options.
FOLLOW-UP TRAP: Tweaking ATPG switches before checking architecture inputs.METRIC -> MECHANISM -> EVIDENCE -> FIX -> REGRESSIONSCAN INSERTION FLOW
scan-ready RTL -> scan replacement -> stitch chains -> DRC -> ATPG handoffState metric, lot/corner context, and pattern tag with every claim.
Treat timing, power, and quality as one signoff problem.
Chasing coverage without legality checks.
Ignoring test-power side effects of pattern changes.
Debugging silicon without reproducible tags.