Die and core
Beginner
The die is the whole tiny slice of silicon that becomes one chip. The core is the inner area that holds the working parts, with a border around it.
Novice
The die is the whole rectangle of silicon cut from the wafer. The core is the inner rectangle where the logic goes. The border between them holds the chip’s connection pads, power wiring around the edge, or simply clearance.
Expert
Set directly as rectangles (initialize_floorplan -die_area/-core_area, or DIE_AREA/CORE_AREA in OpenROAD-flow-scripts) or derived from a target utilization, aspect ratio and margin. The die may also be a right-angled polygon, such as an L shape. Core edges should line up with the placement-site and routing-track grids so rows and pins line up with them.
Explained in Floorplanning (Design Flow).
See also: Utilization (placement density), Aspect ratio.