Allegro PCB Design Tutorial

Creating Elliptical Slot

Most vias, or the holes in the components for that matter are circular. Creating the circular pads with a circular drill is simple - all you need to do is specify the radius of the drill and the size of the pad ( Off course in addition to Solder Mask and solder paste sizes).

The process is similar if we wish to create a circular pad.

You need to navigate to Cadence -> Release 16.3 -> PCB Editor Unitilies -> Pad Designer.

It prompts a window which allows you to design a new Pad.

Navigate to Parameters and select Oval Slot under Hole Type. Specify the Slot Size X and Slot Size Y. Allegro also allows you to specift offset, though you will not need it im most case.

Next Navigate to the Layers.

With Begin Layer Selected, select oblong under Geometry in the Regular Pad. Now specify the Width and the Height. In our case, for example, a width of 50 and a height of 150 could be suitable values ( 25 mils more than the drill). Repeat the same thing for the Default Internal and teh End Layer.

You will also need to specify the SolderMask_Top , Solderdemask_Bottom as well as the PasteMask Top and PasteMask Bottom figure.

We have created youtube for it.

Not that when you generate gerber file, the slots do not get included. To generate the oval / oblong slot in the drill list, you need to go to Manufacture -> NC -> Drill Route. This will generate a drill file that will contain the oblong drills. The Manufacture -> NC -> NC Drill does not contain the oval drills. You may also like to generate a separate report of the slots using Tools -> Report -> Slot report.