CDC/RDC Interview Q&A Bank

What this topic teaches

CDC/RDC Interview Q&A Bank focuses on closing CDC/RDC risk with mechanism-level reasoning. Deliberate practice across metastability, protocols, reset sequencing, and waivers builds repeatable senior-level responses. Senior signoff depends on proving behavior with targeted evidence, not just clearing tool warnings.

The senior-engineer question

When answer completeness, conceptual correctness, practical judgment regresses, can you classify the hazard, identify accountable owners, and choose the smallest fix or waiver backed by evidence?

CDC/RDC SIGNOFF FLOW — CDC/RDC Interview Q&A Bank

crossing inventory + reset map
          |
          v
crossing classification (level/pulse/bus/reset)
          |
          v
structure + protocol + reset checks
          |
          v
critical issues + waiver review
          |
          v
fix / validate / regress / signoff

Picture the crossing behavior

Draw the behavior before touching tools. These visuals are the expected whiteboard baseline for reviews and interviews.

Answer quality checklist

strong answer:
mechanism first, metric second, evidence third, decision last

Crossing sequence

CROSSING FLOW — CDC/RDC Interview Q&A Bank

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

Key metric: answer completeness, conceptual correctness, practical judgment

Ownership layers

CDC/RDC OWNERSHIP LAYERS — CDC/RDC Interview Q&A Bank

layer                 owns                            common failure
------------------    -----------------------------   -----------------------------
design intent         crossing architecture           wrong topology selected
protocol semantics    req/ack, fifo, ordering        liveness/deadlock bugs
reset behavior        assert/deassert sequencing      boot instability
analysis setup        tool rules + waivers            false confidence
signoff governance    risk acceptance + dashboard     stale critical waivers

Evidence to collect

• Primary metric: answer completeness, conceptual correctness, practical judgment.

• Primary artifact: Q&A bank, scoring rubric, replay notes.

• Owners to involve: candidate, mentor, hiring team.

• At least one reproducer tied to mode/reset/traffic context.

• Decision record: fix, waive, or escalate with rationale.

Ownership map

OWNERSHIP MAP — CDC/RDC Interview Q&A Bank

artifact                  owner
----------------------    -------------------------
design intent           candidate
verification evidence   mentor
signoff decision        hiring team

Every open CDC/RDC issue needs one accountable owner before waiver or fix.

Subpages in this topic

Each topic includes mechanism, I/O contract, metrics, debug, worked example, pitfalls, interview drills, checklist, theory, design tradeoffs, expanded case study, walkthrough, comparison matrix, software view, and silicon impact.

Key takeaways

• Classify crossing/reset hazards before proposing fixes.

• Pair structural results with protocol/reset behavioral proof.

• Treat waivers as bounded risk contracts, not cleanup shortcuts.

Common pitfalls

• Mass-waiving warnings near tapeout.

• Assuming local IP cleanliness guarantees SoC behavior.

• Skipping reconvergence and reset stress after CDC fixes.

Q&A drill guide

INTENT -> FAILURE MODE -> EVIDENCE -> FIX/WAIVER -> REGRESSION

Sketch while answering

INTERVIEW FLOW

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

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.