PADS Tips and Tricks – Changing Trace Width While Routing

This Tip is Shared by Yan Killy, Technical Marketing Engineer

There are technology and fabrication reasons why designers on occasion need to change the width of a trace during interactive routing.  In PADS, you can easily accomplish this with settings in Design Rules and the use of Modeless Commands.

Using Design Rules you set can up the trace width range for all nets or one net in particular. In the Design Rules dialog box, under Clearance is the Trace width rules, where there are three settings: Minimum, Recommended, and Maximum. When you start routing a Trace it will always start by using Recommended value. To change the width, start routing and place a corner then type ‘W’ on the keyboard and enter different value for the trace width. As you continue routing this trace, it will use this new trace width value until you will change it again.

If your setting for the Trace width were 6 mils for Minimum, 12 mils for Recommended, and 25 mils for Maximum, your Trace will start routing at 12mils and then you can change to any value that satisfy Minimum/Maximum settings by using the “W” modeless command.

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4 thoughts about “PADS Tips and Tricks – Changing Trace Width While Routing
  • Mentor EE 7.9.5 seems not to know that command. I did it in past with right mouse button an Change Width, but These commands are gray and can not be accessed. I have now idea how it happened. I’m used to deal with unexpected behavior of mentor, but if you are working under pressure it is sometimes very difficult to stay calm. Help is very appreciated.

  • Unfortunately, there doesn’t seem to be a modeless command to change the “recommended” (i.e. default) trace width.
    Using the w modeless command, you have to press w and enter the width again for every trace you route.
    The only way to change the default width for all traces is to drill into
    Setup:Design Rules:Default:Clearance
    and change the recommended width there.
    If I’m mistaken, please feel free to correct me!

  • In Layout, right click, Filter, select Traces Only, window around entire board, or section (traces will highlight), right click again, Trace Properties window pops up, type in Width in box. Note: If you get Wrong Width Value popup, click on Rules, Clearance, and change Recommended Width Values, OK, then go back to Trace Properties window and try again.

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This article first appeared on the Siemens Digital Industries Software blog at https://blogs.sw.siemens.com/pads/2013/01/03/pads-tips-and-tricks-changing-trace-width-while-routing/