1. Purpose and scope
Each die has passed its own sign-off and the package design is frozen, but neither proves that the assembly works. A net can be swapped between die and interposer, a stacked die can overlap a keep-out region, a link can pass at each end but fail across the channel, and heat from one die can push its neighbour out of its timing corner. Multi-die sign-off finds these problems while they can still be fixed in a database rather than in hardware.
The stage covers assembly-level connectivity and design rule checks across dies, interposer or bridge and substrate; timing across the die-to-die links with the package in the path; power integrity from board to transistor; thermal analysis with final power maps; and mechanical stress at bumps and joints. It ends with release of every die database to its foundry and the interposer and substrate manufacturing data to their suppliers.
Because dies may go to different foundries at different times, the stage also manages the release sequence, so that no die is released against a package or neighbour version that later changes.
12 more sections for registered members.