Congestion Analysis
Predict routing risk before it becomes a blocker.
Overview
Congestion analysis estimates where routing demand exceeds available tracks. It is most valuable early, during floorplanning and placement.
Hotspots often appear near macros, narrow channels, or high pin-density blocks.
What to Look For
High demand-to-supply ratios on horizontal and vertical layers.
Pins clustered in a small area with limited routing tracks.
Long detours that inflate RC delay and timing risk.
Mitigation
Add whitespace or widen channels between macros.
Spread high-fanout logic or insert buffers to reduce density.
Reserve routing resources for clocks and critical nets.