How to Set PCB Via Tenting in PCB Design Software

Introduction

Via tenting refers to covering the via pads with ink, no solder on the pads, a process widely used in most circuit boards.

It's a critical part of PCB design, protecting the vias and enhancing the board’s durability and performance. In this guide, we'll show you how to configure PCB via tenting in commonly used software such as Altium Designer (AD) and Protel 99 to ensure your Gerber files meet the required manufacturing standards.

Inspection standard: The via pads should not adhere to solder either through reflow soldering or manual soldering.

Gerber Output and Via Tenting

For PCBs ordered with Gerber output, the "Via Tenting" or "Via Expose" options selected on the JLCPCB ordering platform are not applicable. The Gerber file determines the final via properties, so it’s crucial to configure your files correctly before submission.

Why Via Tenting is Important

Via tenting helps to prevent contaminants from affecting the vias, improving the overall reliability of the circuit board. By default, AD and Protel 99 export vias as exposed, so you'll need to adjust the settings to apply tenting before generating Gerber files. Here’s how you can do it.

Via Tenting in Altium Designer (AD)

1. Open your PCB design in Altium Designer. Double-click on any via to open the properties. Check the boxes in front of "Force complete tenting on top" and "Force complete tenting on bottom".

• "Force complete tenting on top " means the vias will be covered on the top layer.

• "Force complete tenting on bottom " means the vias will be covered on the bottom layer.

2. Right-click the via you just edited and choose "Find Similar Objects" from the context menu.In the dialogue box, check both boxes next to "Solder Mask Tenting - Top/Bottom" and click OK to apply the changes.

By completing these steps, your Gerber file will contain tented vias when exported.

Via Tenting in Protel 99

1. Open your PCB design in Protel 99 and go to Design → Rules.In the rules menu, select "Solder Mask Expansion" and double-click to open the settings.

Configure Tenting Settings:

2. In the Solder Mask Expansion Rule menu, follow the displayed instructions to complete all via tenting settings.

Click OK to save the settings, and proceed to export the Gerber file.

Following these steps will ensure that the vias are tented in your Protel 99 design, aligning with manufacturing requirements.

Conclusion

Mastering via tenting is key to producing high-quality, reliable PCBs. By setting up via tenting in Altium Designer or Protel 99, you can ensure your Gerber files are correctly configured for manufacturing. Properly tented vias will enhance the lifespan and performance of your PCB, protecting it from environmental factors.

For the best results, always review your via tenting settings before submitting your Gerber files to manufacturers like JLCPCB.