Teardrops on a 2D PCB
What are Teardrops?
Teardrops are small shapes added where a trace connects to another object—such as an SMD pad, PTH pad, via, or wider trace. They make these connections stronger and less likely to break from issues like manufacturing tolerances or drilling misalignment.
Why Use Teardrops?
When making a circuit board, small mistakes can weaken connections. Teardrops help smooth out these connections, making them less likely to break. This is especially helpful in high-density boards or designs that may face mechanical stress.
How Do Teardrops Work?
You can add teardrops through the Design Rules dialog using 4 rules - one for each connection type:
- Via Teardrop
- PTH Pad Teardrop
- SMD Pad Teardrop
- Trace-to-Trace Teardrop (Taper)
Each rule lets you define:
- Width and Length: As a percentage of the connected object’s size.
- Violation Mode: Choose to either Ignore or Avoid violations.
- Auto-generate: Automatically apply teardrops to relevant connections.
You can also manually control teardrops in the Inspector, under Wire Properties. Toggle the Teardrop field on or off for selected wires.
Manual settings take effect only if teardrop rules are enabled. If the rules are off, teardrops won’t appear even if the field is set to On.
Limitations:
- Wire property behavior: Teardrop property appears on all wires, but it only works on connections with vias, SMD pads, PTH pads, or wide traces.
- Teardrop updates: If you delete components directly from a 2D PCB that is not linked to a schematic, teardrops won't be removed until you regenerate them by moving traces or running design rules. This happens because an unlinked 2D PCB cannot trigger design rules appropriately.
- Ansys export: Exporting a PCB with teardrops to Ansys is not supported. Use ODB++ export instead.
- Curve wires: Teardrops cannot be applied to curved wires due to current technical limitations.