DFT / ATPG · All levels
Test Logic Floorplan: Reports & Metrics
Reports & Metrics for Test Logic Floorplan.
Reports and metrics
Reports & Metrics for Test Logic Floorplan focuses on compression logic placement quality, test route detours, floorplan DFT ECO count. The goal is to convert metric movement into mechanism, owner, and release decision.
A report should support a release decision for compression logic placement quality, test route detours, floorplan DFT ECO count. One headline number is rarely enough without setup tags and bucket-level evidence.
Metric movement
METRIC GRAPH - compression logic placement quality, test route detours, floorplan DFT ECO count
quality metric
^
| target
| - - - - - - -
| o after fix + regression
| o
| o baseline
| o regressed run
+--------------------------------------> closure iteration
input audit focused fix signoff review
Readout:
- explain what moved, why it moved, and who approved itDistribution view
PATTERN HISTOGRAM - Test Logic Floorplan
pattern count
| ***
| *******
| ***********
|************* <- high-volume tail (optimize here)
+--------------------> pattern buckets
smoke stuck-at transition diagnosis
Balance quality and tester limits together.Track compression logic placement quality, test route detours, floorplan DFT ECO count by context and pattern class.
Review trend and bucket detail together.
Keep quality, timing, and power metrics in one dashboard.
Store each metric next to the artifact and run tag.
DFT deep dive
Physical integration quality decides whether DFT architecture survives implementation realities.
Concept diagram
PHYSICAL DFT FLOW
chain planning -> floorplan placement -> route -> test timing/power validationMetric graph
ROUTING BURDEN
poor chain order -> longer routes -> more hold buffersReports and artifacts
scan physical wirelength
congestion heatmap
test clock skew
handoff issue tracker
Mini case study
Late scan reorder reduced route detours and eliminated a major shift hold cluster before signoff.
Debug branches
Correlate chain order with congestion
Place compression logic near chain clusters
Keep DFT-PD handoff versioned
Senior review question
Ask: what evidence proves this DFT decision is safe for production?
Key takeaways
State metric, lot/corner context, and pattern tag with every claim.
Treat timing, power, and quality as one signoff problem.
Common pitfalls
Chasing coverage without legality checks.
Ignoring test-power side effects of pattern changes.
Debugging silicon without reproducible tags.