Chapter 5
Working with Traces and Copper
5-2
ni.com
operations on traces, be sure to select either the appropriate segment or, if
you wish, the whole trace.
Clearance is the distance from the edge of the board and around pads and
traces that is to be kept free of any other elements. Trying to run a trace
through a clearance, or trying to place a part so that a pad is put within a
clearance, for example, results in an error. The board outline clearance is
defined in the
PCB Properties
dialog box. Clearances for other copper
elements are defined in the
General
tab of the element’s properties. Refer
to the
Viewing and Editing Copper Properties
section for more
information.
To view clearances, choose
View»Clearances
. The clearances are shown
as fine blue lines around pads and traces.
Working with Traces
Ultiboard’s default trace measures 10 mil wide and has a clearance of
10 mil. Clearances are measured from the outside edge of an object: a
10 mil trace with a 5 mil clearance would measure 20 mil across from edge
to edge (5 mil clearance on one side, the 10 mil trace, and 5 mil clearance
on the other side).
Placing a Trace: Manual Method
When you place a trace manually, you click pads and vias, and you must
also click the trace’s pivot points. This means that you have the most
control over where the trace lies, but you must avoid placing the trace
through parts and over other traces. If you try to place a manual trace
through a part or over another trace, an error is generated in the
DRC
tab
of the
Spreadsheet View
.
Complete the following steps to place a trace manually:
1.
Choose a copper layer.
2.
Select or enter the desired trace size in the
Draw Settings
toolbar.
3.
Choose
Place»Line
.
4.
Click a pad on the board. The net the pad is a part of is highlighted, and
the pads in the net are each marked with an X.
5.
Make your way to the next pad in the net. Remember to avoid parts and
other traces. Click to fix the trace to the board each time you change
direction.
