Area, Power & Timing Tradeoffs: Tricky Q&A

Section Q&A bank

Use these drills after completing all topics in Area, Power & Timing Tradeoffs. Answer with run context, metric, mechanism, owner, fix, and regression.

How does VT mix interact with hold risk?

[INT][SYNTH][AREA-POWER-TIMING]

Q: How does VT mix interact with hold risk?

A:
Aggressive LVT use can improve setup but reduce hold margin and increase leakage, so setup/hold split must stay balanced.

FOLLOW-UP TRAP: Optimizing VT for setup only.

What makes a PPA decision 'senior'?

[INT][SYNTH][AREA-POWER-TIMING]

Q: What makes a PPA decision 'senior'?

A:
Choosing a reversible option backed by Pareto evidence, owner alignment, and regression cost awareness.

FOLLOW-UP TRAP: Single-metric optimization heroics.

Q&A drill guide

CONTEXT -> METRIC -> MECHANISM -> FIX -> REGRESSION -> OWNERSHIP

Sketch while answering

PPA TRIAD

timing target <-> power budget <-> area cap

Key takeaways

• State exact run context (RTL, SDC, libs, switches) with every QoR claim.

• Re-run timing, area, and power regressions after each synthesis ECO.

Common pitfalls

• Comparing runs with mismatched constraints or library views.

• Timing-only fixes that violate power or area budgets.

• Skipping equivalence checks after structural changes.