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CDC / RDC · All levels

CDC Review Gate: Step-by-Step Walkthrough

Step-by-Step Walkthrough for CDC Review Gate.

Step-by-step analysis walkthrough

Use this sequence when owning CDC Review Gate in a signoff review.

  1. Inspect warning class and severity.

  2. Trace crossing endpoints and domains.

  3. Check protocol/reset assumptions against spec.

  4. Review synchronizer or FIFO implementation detail.

  5. Run focused assertion or formal check.

  6. Draft fix options with risk and schedule impact.

  7. Execute regression and publish closure memo.

Artifacts to collect

  • review checklist, gate scorecard, escalation log

  • crossing inventory

  • waiver board notes

  • regression report

Decision memo template

diagram
CDC/RDC DECISION MEMO — CDC Review Gate
risk class:
mechanism:
evidence:
fix/waiver:
owners: program lead, CDC owner, integration lead

Reference visuals

Review gate criteria

diagram
Gate inputs:
  - zero critical unowned CDC issues
  - formal/sim evidence for protocol crossings
  - waiver aging below threshold

CDC/RDC deep dive

Signoff is an evidence governance problem across teams.

Concept diagram

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CDC SIGNOFF LOOP

analysis -> triage -> fix/waive -> review gate -> dashboard

Metric graph

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CRITICAL OPEN COUNT

week1 34
week2 22
week3 10
week4 0

Reports and artifacts

  • critical by owner

  • waiver quality

  • review gate status

  • closure trend

Mini case study

Pass rates improved while critical waivers aged out of policy; dashboard exposed hidden risk.

Debug branches

  • Separate quality from quantity metrics

  • enforce waiver expiry

  • run gate checklists consistently

Senior review question

Ask: what evidence proves this risk is closed for silicon, not just tool-clean?

Key takeaways

  • State crossing class, assumptions, and owner with every issue.

  • Run structural and dynamic regressions after each fix.

Common pitfalls

  • Treating all warnings as equivalent risk.

  • Waiving issues without containment evidence.

  • Skipping reset and reconvergence stress after CDC fixes.

Principal CDC/RDC review addendum

Gate reviews align RTL, verification, and signoff evidence before integration milestones to avoid endgame metastability surprises.

Metric: gate pass rate, late-stage CDC churn, review defect leakage

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