The floorplan has no credible space for the proposed power grid. Can macro placement proceed?
From PDVerse PnR Interview Handbook · pdVerse Mentor Guide
Short Answer
Stop or iterate if required PG sources, rings/straps/rails, macro pin access, switch corridors, or via paths cannot fit without destroying signal capacity. Planning must reserve these resources first.
Technical Explanation
A floorplan that works only without power is not physically credible. Verify current and supply assumptions with the power owner, then overlay planning geometry on channels, pins, voltage areas, and routing layers.
Formula Or Decision Rule
Decision rule: demonstrate joint PG and signal feasibility before locking macros.
What To Check
• Warning sign: Schedule pressure defers every power question to a later chapter. • Inspect: choose one affected region, macro, row, pin, path, or net and trace the physical cause. • Correct: Reserve the approved resources, change macro/channel/pin geometry as needed, and rerun floorplan checks.
Command Checks & Actions
• check_design -checks {dp_pre_power_insertion}: runs named design-planning check groups
• report_design -floorplan: reports the floorplan state understood by the tool
• report_congestion -mode summary: reports routing demand, capacity, overflow, or hot spots
Run only the commands needed for this question. Save the report with the floorplan version and analysis context.Healthy, Suspicious & Hard-stop Results
• Healthy: Stop or iterate if required PG sources, rings/straps/rails, macro pin access, switch corridors, or via paths cannot fit without destroying signal capacity. Planning must reserve these resources first. • Suspicious: Schedule pressure defers every power question to a later chapter. • Hard stop: required legality or physical feasibility is missing or unexplained. Reserve the approved resources, change macro/channel/pin geometry as needed, and rerun floorplan checks.
Common Mistake
Do not hide the symptom with an arbitrary utilisation, halo, channel, blockage, pin move, or die-size change. Schedule pressure defers every power question to a later chapter.
What The Interviewer Is Testing
The interviewer is testing whether you can connect “The floorplan has no credible space for the proposed power grid. Can macro placement proceed?” to measurable physical evidence and an owned correction.
Follow-up Question & Model Response
Follow-up probe: What would make you change your decision? Model response: “I would change it if the same controlled rerun shows that schedule pressure defers every power question to a later chapter. I would use the named objects and reports to decide whether to iterate, waive, or return the issue.”
Practical Example
Symptom: Schedule pressure defers every power question to a later chapter. Corrective path: Reserve the approved resources, change macro/channel/pin geometry as needed, and rerun floorplan checks.
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