[DIE]

The die section is used to describe the "name" of the die along with the height, width and center location of the die outline. The acutal die pad openings and coordinates are described in the netlist section.

[DIE]
WIDTH=9220.20
HEIGHT=11226.8
NAME=DIE1G
CENTER=0 0

The CENTER keyword and values are optional. If CENTER is not used, the AIF reader will calculate the center by calculating the extents of the die pad centers and using the center of the die pad extents. This approach works well for digital die where the pads are symmetric around the center but it fails for certain types of pad arrangements -- hence the ability to specify the center if needed.

For a die with symmetrically arranged pads no CENTER is needed as the calculated center and the desired center are the same.

Consider this memory chip die with only one row of pads on the right side of the die. If the CENTER parameter for the outline is not specified then you won't get this relationship between the outline and the die pads. Instead you will get something in the illustration below.

Here is what you will see if the CENTER parameter is not provided. The program will line up the center of the outline with the center of the die pad extents.