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Summary
Teardrops are often added to a routed PCB design to create stronger track-to-pad, track-to-via and track-to-track connections. This is valuable when the the design objects are very small, and is particularly valuable for drilled pads and vias, because mis-alignment between the drill center and the pad/via center can result in the drill hole removing too much of the copper connecting the track to the pad/via.
Teardrops are created by placing a region object at the required location.
Access
To add or remove teardrops to the current PCB, select Tools » Teardrops from the toolbar.
Options/Controls
Teardrops can be added, and their properties defined, as follows:
Working Mode
- Add/Remove - Add or remove teardrops in accordance with the other dialog settings.
Objects
This setting is used in conjunction with those object types enabled in the Scope region of the dialog.
- All - Target either all objects, or
- Selected Only - Only target those objects currently selected in the workspace.
Options
- Teardrop style: The edge of the region object used to create the teardrop can be straight (Line) or Curved.
- Curved - Use a Curved Teardrop style.
- Line - Use a Line Teardrop style.
- Force teardrops - If this option is enabled, Teardrops will be applied to all vias and/or SMD pads - even if this results in a DRC violation.
- Adjust teardrop size - If this option is enabled, the Teardrop size is automatically reduced to meet applicable design rules.
- Generate report - Create a text report listing both successful and unsuccessful teardrop sites.
Scope
Choose which objects to consider for teardrop addition/removal - Vias, SMD Pads, Tracks, and/or T-Junctions - in conjunction with the coarse-level scoping defined in the Objects region of the dialog. When adding Teardrops, you can configure teardrop sizing as follows:
- Via/TH Pad - Specify the length and width of the teardrop as percentages of the via/thru-hole pad diameter (d). The defaults are 30% and
70%
respectively. Click the blue percentage values to change these as required. - SMD Pad - Specify the length and width of the teardrop as percentages of the attached track width (w). The defaults are 100% and 200% respectively. Click the blue percentage values to change these as required.
- Tracks - Specify the length of the teardrop as a percentage of the attached track width (w). The default is
100%
. Click the blue percentage value to change this as required. - T-Junction - Specify the length and width of the teardrop as percentages of the primary track width (w) (the horizontal track in the image). The defaults are 300% and
100%
respectively. Click the blue percentage values to change these as required.
Tips
- Region-based teardrops were introduced in Altium Designer 14.3. In earlier versions teardrops were created from track and arc objects. If required, this style of teardrop can be added or removed by running the Tools » Legacy Tools » Legacy Teardrops command.