Short Circuit Rules

DRC's for Short Circuits.

Short Circuits violations can include unused pins of a fanned out BGA.

Or custom footprints that have two primitives with the same pin number.

Example Datasheet for the QFN shown above suggested using chamfered pads for the corner pins.


Two primitives were used to create chamfered pads, a top layer pad and a region.

Pads that are made up two or more primitives can cause Short Circuit DRCs if the pads have no nets assigned.

The solution is to create a Short Circuit rules to allow primitives with no assigned nets to overlap, using 'Not InAnyNet' 


Allow all No Nets to short together.

This same technique can be used to allow BGAs to be fanned out and pass the DRC checks for short circuits when the pins don't have assigned nets (No Nets).

For a BGA with unused fanned out connections.

Allow for overlapping primitives in the same part (not fanned out)

 

That's It !