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Top 30 Physical Design Interview Questions and Answers (2026)

Coursetron Admin

Thu, 03 Sep 2026

Physical Design Interview Questions — 2026 Edition

Cracking a Physical Design (PD) interview at Qualcomm, Intel, NVIDIA, AMD, or Apple takes more than tool fluency. You need conceptual clarity on floorplanning, placement, CTS, routing, STA, and signoff. Here are the 30 most-asked PD interview questions, grouped by topic.

Floorplanning

1. What is utilization and what is a good target? — Utilization = (std cell area + macro area) / core area. Target 65–75% for advanced nodes.
2. What is aspect ratio and how does it affect routability?
3. How do you place macros? — Pin-side, dataflow, power rings, blockages.
4. What is a power plan? — Power straps, rings, mesh sized for IR drop budget.

Placement

5. Difference between global and detailed placement
6. What is congestion and how to fix it?
7. Scan chain reordering — why and when?
8. What is a buffer tree pre-CTS?

Clock Tree Synthesis

9. CTS goals: skew, insertion delay, latency
10. Useful skew vs zero skew
11. Clock gating effect on CTS
12. OCV-aware CTS for advanced nodes

Routing

13. Layer assignment strategy
14. Antenna effect and fixes
15. Crosstalk delta delay
16. Double patterning constraints (7nm and below)

STA & Signoff

17. Setup vs hold timing — definitions, fixes
18. What is a false path?
19. Multicycle path setup
20. SDC commands you use daily
21. IR drop static vs dynamic
22. EM (electromigration) checks

Tools

23. Cadence Innovus or Synopsys ICC2 — which do you prefer and why?
24. PrimeTime vs Tempus
25. Calibre DRC vs ICV

Scenario-based

26. You have a setup violation on the launch flop. Walk me through the fix.
27. How would you reduce dynamic power by 15%?
28. Macro placement is causing routing congestion. What do you do?
29. What is your debug flow for an IR drop hotspot?
30. How do you handle multi-mode multi-corner (MMMC) analysis?

How to Prepare

Theory alone won’t land the offer. Get hands-on with Innovus + PrimeTime in our VLSI Physical Design Course. We also cover STA depth in our complete VLSI catalog.