Most designs do not require loops. However, some design applications such as shielding signals and ground nets or power nets with partial vias may require them. In the latest PADS Professional VX.2.5 update, users can allow and disallow loops on nets in layout.
When disallowed, all selected nets will prevent loops during interactive routing. Typically, this should be applied for all nets in the design unless there is a need for a loop on specific nets. When allowed, users can interactively route a loop on their selected nets. Once the loop exists, it persists on the net. Users can continue to add loops regardless of the Prevent Loops settings.
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