CDC/RDC Whiteboard Framework: Expanded Case Study

Extended case study

Milestone review flags problem decomposition quality, mechanism-first answer quality around CDC/RDC Whiteboard Framework.

Background

Team believed crossings were stable until stress mode exposed intermittent anomalies.

Symptoms observed

• problem decomposition quality, mechanism-first answer quality regression

• Mismatch between structural report and dynamic behavior

• Waiver debate under schedule pressure

Investigation timeline

1. Freeze design, reset, and tool configuration tags.

2. Reproduce failing scenario with minimized stimulus.

3. Map path/protocol/reset dependencies.

4. Classify root cause and containment options.

5. Execute minimal safe fix.

6. Run stress regression and review board.

Root cause

Root cause links to CDC/RDC Whiteboard Framework: Strong interview answers trace crossing intent, failure mechanism, containment strategy, and signoff evidence in a deterministic sequence.

Fix and validation

• Targeted RTL/protocol/reset correction

• Evidence refresh

• Signoff board decision

Lessons learned

• Treat waivers as temporary risk contracts

• Track owner and expiry

• Regression before closure

CASE STUDY — CDC/RDC Whiteboard Framework
critical issues before / after / signoff

Crossing sequence under stress

CROSSING FLOW — CDC/RDC Whiteboard Framework

source clock domain -> launch signal -> crossing structure -> destination sample
      |                    |                 |                    |
   source FF           protocol           sync / fifo         destination FF

Key metric: problem decomposition quality, mechanism-first answer quality

CDC/RDC deep dive

Interview performance reflects production signoff thinking quality.

Concept diagram

INTERVIEW FLOW

classify -> explain mechanism -> propose fix -> state regression

Metric graph

PRACTICE SCORE

session1 62%
session2 78%
session3 89%

Reports and artifacts

• scenario completion

• answer rubric scores

• trap recovery quality

Mini case study

Candidate gave command-heavy answer but missed risk framing and waiver governance.

Debug branches

• Use mechanism-first structure

• name ownership and evidence

• close with signoff decision

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.