Routing track and pitch
Beginner
An invisible lane on a wiring layer. Wires run along these lanes, which are spaced evenly so wires never get too close.
Novice
One of the evenly spaced lines a wire’s center may run along on a layer. The spacing between tracks, the pitch, is about one minimum wire width plus one minimum gap. The number of tracks that cross a region is how many wires can pass through it.
Expert
Each layer’s track pattern (starting offset, pitch and, on multi-patterned layers, mask color) fixes where wires may go; DEF records it as TRACKS statements built from LEF PITCH. Standard-cell height is quoted in tracks. Pins that sit off the track grid, and layers whose pitches don’t line up, make pin access and via placement harder.
Explained in Routing (Design Flow).
See also: Preferred routing direction, GCell (global routing cell).