Defining the layer stack

Routing and documentation layers are defined in the Layers spreadsheet. Using the spreadsheet, you can define the number of routing layers that will be used for the board.

If you plan to have a board with four routing layers (TOP, BOTTOM, INNER1, and INNER2) and two plane layers (POWER, GROUND), then you need to define the layers in a technology template (.TCH) or a board template (.TPL).

Defining global spacing values

Global spacing values set rules for spacing between the various objects on the board. You can define global spacing values for the board using the Edit Spacing dialog box, which is accessed from the Route Spacing spreadsheet. You can save spacing requirements in a board template (.TPL). Uniform spacing requirements per layer reduce processing time.

Track to Track Spacing

Tracks are defined as routed connections and copper obstacles, such as keepouts and place outlines. Track-to-track spacing specifies the minimum space required between tracks of different nets, and between tracks and obstacles of different nets.

· Track to Via Spacing

Track-to-via (and obstacle-to-via) spacing specifies the minimum space required between vias and tracks of different nets.

· Track to Pad Spacing

Track-to-pad (and obstacle-to-pad) spacing specifies the minimum space required between pads and tracks of different nets.

· Via to Via Spacing

Specifies the minimum space required between vias of different nets.

· Via to Pad Spacing

Specifies the minimum space required between pads and vias of the same net (as well as different nets, which is the usual case). For instance, to keep a distance of 25 mils between your SMT pads and the fanout vias connected to the pads, set Via to Pad Spacing to 25.