What are Gerber Files?

Before diving into panelization, let’s first understand what gerber files are. Gerber files are the industry standard format for describing the layout of a printed circuit board (PCB). They contain all the necessary information for PCB fabrication, including copper layers, solder mask, silkscreen, and drill data. Each layer of the PCB is represented by a separate gerber file.

Gerber files are generated by PCB design software, such as KiCad, Eagle, or Altium Designer, once the PCB design is complete. These files are then sent to the PCB manufacturer for fabrication.

Why Panelize gerber Files?

Panelizing gerber files offers several benefits in PCB manufacturing:

1. Cost Reduction: By combining multiple PCB designs into a single panel, you can reduce the overall manufacturing cost per board. This is because the setup costs for fabrication are spread across a larger number of boards.

2. Improved Efficiency: Panelization allows for faster production as multiple boards can be fabricated simultaneously. This reduces the time required for handling, processing, and testing individual boards.

3. Consistent Quality: When boards are panelized, they undergo the same manufacturing conditions, ensuring consistent quality across all boards in the panel. This minimizes variations that may occur when fabricating boards separately.

4. Simplified Assembly: Panelized boards can be easily assembled using automated pick-and-place machines. The consistent spacing and orientation of the boards in the panel facilitate smooth assembly operations.

Steps to Panelize Gerber Files

Now that we understand the importance of panelizing gerber files, let’s go through the step-by-step process of creating a panel.

Step 1: Prepare the Individual Gerber Files

Before panelizing, ensure that you have the complete set of gerber files for each PCB design you want to include in the panel. These files should be generated from your PCB design software and include all the necessary layers (e.g., copper, solder mask, silkscreen) and drill data.

Step 2: Determine Panel Size and Layout

Decide on the size of the panel based on the dimensions of your individual PCB designs and the manufacturing capabilities of your chosen PCB fabricator. Consider the following factors:

• The maximum panel size supported by the fabricator
• The minimum required spacing between individual boards
• The placement of fiducial markers and tooling holes
• The orientation of the boards in the panel (e.g., horizontal, vertical, mixed)

Create a rough layout of the panel, considering the above factors and ensuring optimal utilization of the panel space.

Step 3: Import Gerber Files into Panelization Software

Use a panelization software or a gerber editor that supports panelization features. Popular options include:

• Gerbv
• CAM350
• CircuitCAM
• LPKF CircuitPro

Import the individual gerber files for each PCB design into the panelization software.

Step 4: Arrange and Align the Boards

Arrange the individual PCB designs within the panel layout according to your planned arrangement. Ensure that there is sufficient spacing between the boards to accommodate the fabrication process, including routing and separation.

Align the boards precisely using the software’s alignment tools. Maintain consistent orientation and spacing throughout the panel.

Step 5: Add Fiducial Markers and Tooling Holes

Fiducial markers are small, round pads placed on the panel that serve as reference points for aligning the panel during fabrication and assembly. Place fiducial markers at strategic locations on the panel, typically near the corners or edges.

Tooling holes are used to secure the panel during fabrication and assembly processes. Add tooling holes to the panel, ensuring they are positioned accurately and do not interfere with the individual PCB designs.

Step 6: Add Mousebites or V-Scoring Lines

To facilitate the separation of individual boards from the panel after fabrication, you need to add mousebites or v-scoring lines.

• Mousebites: These are small, perforated holes placed along the edges of each individual board. They allow for easy snapping of the boards from the panel.
• V-Scoring: V-scoring involves creating shallow grooves along the edges of each board, making it easier to break them apart from the panel.

Determine the appropriate size and spacing of mousebites or v-score lines based on the thickness of your PCB and the recommendations of your fabricator.

Step 7: Generate the Panelized Gerber Files

Once you have arranged the boards, added fiducial markers, tooling holes, and mousebites or v-scoring lines, generate the panelized gerber files.

Most panelization software allows you to export the panel as a set of gerber files, similar to the individual PCB gerber files. Ensure that all layers are included in the exported files.

Step 8: Verify and Review the Panelized Gerber Files

Before sending the panelized gerber files to the fabricator, thoroughly verify and review them. Check for any discrepancies, overlaps, or misalignments in the panel layout.

Use a gerber viewer to visualize the panel and ensure that all layers are correctly aligned and positioned. Pay attention to the placement of fiducial markers, tooling holes, and mousebites or v-scoring lines.

Step 9: Send the Panelized Gerber Files to the Fabricator

Once you have verified the panelized gerber files, send them to your chosen PCB fabricator. Provide any additional instructions or specifications required for the manufacturing process.

Communicate clearly with the fabricator about your panel requirements, including the desired material, thickness, surface finish, and any special considerations.

Tips for Successful Panelization

Here are some additional tips to ensure successful panelization of your gerber files:

1. Keep the panel balanced: Arrange the individual PCB designs symmetrically within the panel to maintain balance during fabrication and assembly processes.

2. Consider panelization early: Plan for panelization during the PCB design stage itself. This allows you to optimize the layout and spacing of the individual boards, making panelization easier and more efficient.

3. Follow fabricator guidelines: Consult with your PCB fabricator and follow their specific guidelines for panelization. They may have recommendations for panel sizes, spacing, and other requirements based on their manufacturing capabilities.

4. Test the panelized design: If possible, request a sample panel from the fabricator before mass production. This allows you to verify the quality and functionality of the panelized boards and make any necessary adjustments.

5. Use a checklist: Create a checklist of all the steps involved in panelization to ensure that you don’t miss any crucial aspects. This helps maintain consistency and reduces the chances of errors.

Panelization Software Comparison

To help you choose the right panelization software for your needs, here’s a comparison table of some popular options:

Software	Platform	Key Features	Price
Gerbv	Windows, Mac, Linux	Open-source, supports multiple file formats	Free
CAM350	Windows	Advanced panelization tools, DFM analysis	Paid
CircuitCAM	Windows	User-friendly interface, supports various CAM formats	Paid
LPKF CircuitPro	Windows	Comprehensive panelization features, intelligent routing	Paid

Frequently Asked Questions (FAQ)

1. What is the recommended spacing between individual boards in a panel?
   The recommended spacing between individual boards depends on the PCB thickness and the fabricator’s guidelines. Typically, a minimum spacing of 2-3mm is suggested, but it’s best to consult with your fabricator for their specific recommendations.

2. Can I panelize boards of different sizes and shapes?
   Yes, you can panelize boards of different sizes and shapes within the same panel. However, it’s important to ensure that the panel layout is balanced and the boards are arranged efficiently to maximize the utilization of the panel space.

3. What are the advantages of using mousebites over v-scoring for board separation?
   Mousebites offer several advantages over v-scoring:

4. Mousebites allow for cleaner and more precise board separation.
5. They reduce the risk of damaging the boards during the separation process.

6. Mousebites provide better control over the breakaway points, ensuring consistent results.

7. Can I panelize multi-layer PCBs?
   Yes, multi-layer PCBs can be panelized just like single-layer boards. The panelization process remains the same, but you need to ensure that all layers of the individual boards are properly aligned and positioned within the panel.

8. How do I choose the right panel size for my PCB design?
   When choosing the panel size, consider the following factors:

9. The dimensions of your individual PCB designs.
10. The maximum panel size supported by your fabricator.
11. The number of boards you want to include in a single panel.
12. The spacing requirements between boards and the placement of fiducial markers and tooling holes.
    It’s recommended to discuss the panel size with your fabricator to ensure it aligns with their manufacturing capabilities.

Conclusion

Panelizing gerber files is a crucial step in PCB manufacturing that offers numerous benefits, including cost reduction, improved efficiency, consistent quality, and simplified assembly. By following the step-by-step process outlined in this guide and considering the tips and recommendations provided, you can successfully panelize your gerber files and optimize your PCB production.

Remember to work closely with your PCB fabricator, follow their guidelines, and thoroughly verify the panelized gerber files before sending them for manufacturing. With the right approach and attention to detail, you can ensure the successful fabrication of your panelized PCBs.