Electronic – How to route signals across to a breakoff tab


I have a small circuit board that will be paneled with a breakoff tab that allows for easy handling during assembly.

Currently we just V-Score the square breakoff tab, but we're trying to find a way to route signals across the divider to a programming header on the tab. Is there a way to create a snap off tab that has about 8 thin signal traces routed across to it?

Best Answer

This is a method successfully used for break-away tabs with programming headers:

Break-away Tabs

The points of note are:

  • Drilled holes for convenient break-away
  • Traces are 10 mils, with a 6-mil neck at the break line: This provides a natural strain point on the copper trace, so it breaks cleanly right there.
  • A corner on each trace, each side of the break-away holes. This ensures that even if a particular trace breaks badly, the damage is constrained to the immediate part of the trace up to the corner.

This has worked reliably for a bunch of boards, always broken by hand, not necessarily carefully.