Chapter 7
Autorouting and Autoplacement
©
National Instruments Corporation
7-11
4.
The
Automatic Testpoint Placement Setup
dialog box disappears
and one test point is placed on or near each net on your board. If placed
near an existing net, the test point will be automatically connected.
5.
Results of testpoint placements, including a list of any nets which the
router could not connect, will appear in the
Results
tab of the
Spreadsheet View
. You can click on an error to go to the unrouted
testpoint.
Controlling the Routing Functions
Router functions are controlled through the
Routing Options
dialog box,
which is displayed when you choose
Autoroute»Autoroute/place
Options
.
Routing Options: General Tab
Complete the following steps to set up general routing options:
1.
Select the
General
tab in the
Routing Options
dialog box.
2.
Complete the following fields in the
Routing
area:
•
Routing Mode
—Select
Gridbased
, to place the traces on a grid;
Gridless
to place them off the grid; or
Progressive
which will
attempt to place the traces on a grid, and then place those that
remain off the grid.
•
Grid Type
—Select
English
- the router grid will be some
sensible number of mils (10 mils, 20 mils, etc.); or
Metric
- the
router grid will be some sensible number of millimeters (0.2 mm,
0.3 mm, etc.); or
Board Settings
- Ultiboard will choose either
English or Metric, depending on the units Ultiboard is using. This
setting is independent of the
Routing Mode
setting in the
Routing
area.
•
Optimization Pass
checkbox—Enable to permit router passes
that will optimize the placement of the traces.
3.
Complete the following fields in the
Settings
area:
•
Via Grid
—Select
100 mil standard
, which places the vias on a
100 mil grid;
50 mil standard
, which places the vias on a 50 mil
grid;
25 mil standard
, which places the vias on a 25 mil grid; or
None
, which will not place the vias on any grid. The optimal grid
size is determined on-the-fly by Ultiboard during the routing
process; if it differs from the
Via Grid
setting, vias will be placed
at the grid point closest to the 100, 50 or 25 mil setting.
