what is DEF file in vlsi?
DEF’s full form is Design Exchange Format (DEF). It is used to represent the Physical layout of an Integrated Circuit (IC) in ASCII format.
Basically, the DEF file contains information about where macros, standard cells, I/O pins, and other physical things should be placed. It includes all coordinate information for any designed physical shape.
Internal connectivity, grouping information, and physical limitations are contained in the logical design data, whereas routing geometry, placement information, and orientation are contained in the physical design data.
DEF is a source of input for a number of phases. In order to offer details on the macro location, IO ports, and block shape, Floorplan DEF is provided during the import design step.
DEF contains the following information:,
- Die Area
- Macros
- I/O Pins
- Metal layers
- Blockages
- Slots
- Tracks
- Fills
- Nets
- Vias
DEF file has two main things logical and physical design data Logical design data include internal connectivity which is represented by netlist, grouping information, and physical constraints, while Physical design data information includes placement location and orientation of geometry.
