The AIF database begins with a root AIF object which has some basic properties. This is shown below.

(AIF
 (Version 3.0)
 (Units MICRONS)
 (Precision 4)
)

The root object identifies this file as AIF version 3.0, sets the units and the precision of the values that follow.

AIF Spaces

The AIF III database uses four separate "spaces" each having its own purpose.

Layspace

contains layer definitions, which define the cross-sectional properties of the design.

DefSpace

contains template definitions for those design objects which require them, such as pads and package definitions.

RefSpace

contains instances of design objects from DefSpace along with design objects which require no template, such as wires.

UsrSpace

is used to define custom properties and other user-specific data. The format of UsrSpace is not yet finalized and remains unsupported in this first beta version.

Layer Space

LaySpace has a very simple structure, just defining layer names and states at this time. We may add additional layer properties as needed in the future. (e.g. a type such as signal, plane, mechanical etc...)

(LaySpace
 (Layer
  (Name WBT)
  (Color 255 204 128)
  (Visible YES)
 )
 (Layer
  (Name M1)
  (Color 255 0 0)
  (Visible YES)
 )
 (Layer
  (Name M2)
  (Color 0 0 255)
  (Visible YES)
 )
)

Name

A string. If it includes spaces (which we don't recommend) it must be quoted.

Color

layer color. This is a RGB triplet where 0 0 0 = black and 255 255 255 = white.

Visible

YES or NO. Primarily for the display tool to determine whether to show this layer or not.