CDC Tool Flow: Interview Drills

Interview drills

Interview Drills for CDC Tool Flow focuses on analysis runtime, violation classification completeness, delta noise between runs. The goal is to convert issue observations into mechanism-backed closure decisions.

PROMPT
You see analysis runtime, violation classification completeness, delta noise between runs in CDC Tool Flow. Explain root cause and signoff decision.

STRONG ANSWER
1. Names crossing/reset class and context.
2. Explains Robust CDC signoff combines structural analysis, protocol checks, reset analysis, and targeted formal/simulation evidence with consistent setup tagging.
3. Requests tool run manifest, CDC config files, violation triage sheet.
4. Chooses fix/waiver/escalation with regression plan.

WEAK ANSWER
Lists tool commands or generic advice without mechanism and risk framing.

Diagram to draw on whiteboard

CDC signoff stack

structural CDC scan
    + protocol assertions
    + reset-domain analysis
    + waiver review gate
    = signoff decision

Debug tree to narrate

ROOT-CAUSE TREE — CDC Tool Flow

crossing failure observed
        |
   reproducible?
     /        \
   no          yes
   |            |
stress mode   classify issue
expansion       /      |      \
            synchronizer protocol reset/reconvergence
                 |         |           |
            MTBF fit    liveness    release ordering

CDC/RDC deep dive

Signoff is an evidence governance problem across teams.

Concept diagram

CDC SIGNOFF LOOP

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

Metric graph

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

Robust CDC signoff combines structural analysis, protocol checks, reset analysis, and targeted formal/simulation evidence with consistent setup tagging.

Metric: analysis runtime, violation classification completeness, delta noise between runs