Routing the board manually

When you view the board before you’ve done any routing, you’ll see that the parts have many fine lines running between them. These lines are known as a ratsnest. A ratsnest represents the connections that need to be routed to form the necessary tracks on the board. A connection is an electrical path between two pins: a ratsnest represents an unrouted connection, while a track represents a routed connection.

Checking the board outline, via definitions, and

routing and via grids

Before you route, you should check the settings for the board outline, vias, routing grid, and via grid.

· Verify that the board outline has a desirable amount of internal clearance, that there is only one board outline, and that it is on the global layer.

· Inspect the vias in the Padstacks spreadsheet to make sure that they are the right size and on the correct layers.

· Verify that the routing grid and via grid match for the placement of tracks.

Loading a routing strategy file

A routing strategy file determines which default routing layers to use, when to use vias, which direction the track should travel, which colors to use for routes, and the size of the active routing window.

Changing board density using routing strategy files

If your board is too dense in certain areas (indicated as dark red in the density graph), you can improve the density by experimenting with different routing strategy files or changing the placement. For example, you may want to add layers or change track width or track spacing rules.

To experiment with different routing strategy file

1 With the density graph window displayed, from the File menu, choose Load. The Load File dialog box appears.

2 Locate and select a strategy file (.SF), then choose theOpen button. The density graph redraws itself, presenting new board density data resulting from loading the strategy file.