What is a PCB Panel?

A PCB panel, also known as a PCB array or PCB matrix, is a larger board that contains multiple individual PCBs. The panel is designed to optimize the manufacturing process by allowing several PCBs to be fabricated, assembled, and tested simultaneously. After the assembly process is complete, the individual PCBs are separated from the panel through a process called depaneling or singulation.

The Importance of Choosing the Right PCB Panel Size

Selecting the appropriate PCB panel size is essential for several reasons:

1. Cost-effectiveness: Utilizing a standard panel size that is compatible with the manufacturing equipment can minimize material waste and reduce production costs.
2. Production efficiency: Choosing a panel size that maximizes the number of PCBs per panel can streamline the fabrication and assembly process, resulting in faster turnaround times.
3. Compatibility: Ensuring that the panel size is compatible with the assembly equipment and processes, such as pick-and-place machines and reflow ovens, is crucial for smooth and reliable production.

Standard PCB Panel Sizes

While there is no universally accepted standard for PCB panel sizes, there are several commonly used dimensions in the industry. These sizes have been adopted by manufacturers to ensure compatibility with their equipment and to optimize production efficiency. Let’s take a look at some of the most popular standard PCB panel sizes:

1. 18″ x 24″ (457mm x 610mm)

The 18″ x 24″ panel size is one of the most widely used in the PCB industry. It offers a good balance between panel utilization and compatibility with various manufacturing processes. This size is particularly suitable for medium to large-scale production runs.

2. 21″ x 24″ (533mm x 610mm)

The 21″ x 24″ panel size is another popular choice among PCB manufacturers. It provides a slightly larger area compared to the 18″ x 24″ size, allowing for more PCBs to be accommodated on a single panel. This size is often used for high-volume production and is compatible with most assembly equipment.

3. 12″ x 18″ (305mm x 457mm)

The 12″ x 18″ panel size is commonly used for smaller PCB designs and lower-volume production runs. It is a cost-effective option for prototypes and small batches, as it minimizes material waste and is compatible with smaller assembly equipment.

4. 16.5″ x 22.75″ (419mm x 578mm)

This panel size, also known as the “16 up” size, is often used in the North American market. It offers a good compromise between panel utilization and compatibility with standard assembly equipment.

Factors to Consider When Choosing a PCB Panel Size

When selecting a PCB panel size for your project, there are several factors to consider:

1. PCB design dimensions: The size and shape of your individual PCB designs will influence the panel size selection. You should aim to maximize the number of PCBs per panel while leaving sufficient space for tooling, handling, and depaneling.
2. Production volume: The expected production volume plays a significant role in determining the panel size. For high-volume runs, larger panel sizes like 18″ x 24″ or 21″ x 24″ are more suitable, as they allow for more PCBs per panel and faster throughput.
3. Manufacturing capabilities: It is essential to consult with your PCB manufacturer to understand their equipment capabilities and limitations. Some manufacturers may have specific panel size preferences or restrictions based on their machinery and processes.
4. Assembly requirements: Consider the assembly process and equipment that will be used for your PCBs. Ensure that the chosen panel size is compatible with the pick-and-place machines, reflow ovens, and other assembly equipment to avoid any issues during production.
5. Material utilization: Optimize the panel layout to minimize material waste. Efficient panel utilization not only reduces costs but also contributes to environmental sustainability.

PCB Panelization Techniques

To maximize the benefits of using standard PCB panel sizes, various panelization techniques can be employed. These techniques ensure that the individual PCBs can be easily separated from the panel after assembly. Some common panelization methods include:

1. V-scoring: V-scoring involves creating V-shaped grooves along the edges of the individual PCBs. These grooves allow for easy separation of the PCBs from the panel by applying pressure or using a depaneling machine.
2. Tab routing: In tab routing, small tabs are left connecting the individual PCBs to the panel. These tabs can be easily broken off after assembly, separating the PCBs from the panel.
3. Perforated lines: Perforated lines, also known as mouse bites, are small holes drilled along the edges of the individual PCBs. These holes create a weakened line that allows for easy separation of the PCBs from the panel.

Frequently Asked Questions (FAQ)

1. Q: Can I use custom panel sizes for my PCB project?
   A: While it is possible to use custom panel sizes, it is generally recommended to stick with standard sizes. Custom panel sizes may incur additional costs and lead to longer lead times, as they may require special tooling and setup. However, if your project has specific requirements that cannot be met with standard panel sizes, discuss the options with your PCB manufacturer.

2. Q: How do I determine the best panel size for my PCB design?
   A: To determine the best panel size, consider factors such as your PCB dimensions, production volume, manufacturing capabilities, and assembly requirements. Consult with your PCB manufacturer to discuss your specific needs and obtain their recommendations based on their experience and equipment.

3. Q: What is the minimum spacing between individual PCBs on a panel?
   A: The minimum spacing between individual PCBs on a panel depends on the manufacturing capabilities and the panelization technique used. Generally, a spacing of 2-5mm is recommended to allow for proper tooling and separation of the PCBs. However, it is best to consult with your PCB manufacturer for their specific guidelines.

4. Q: Can I mix different PCB designs on the same panel?
   A: Yes, it is possible to mix different PCB designs on the same panel, a technique known as “mixed panelization.” This approach can be cost-effective for low-volume production or when you have multiple PCB designs that share similar specifications. However, ensure that the designs are compatible in terms of thickness, material, and other manufacturing requirements.

5. Q: How does the panel size affect the cost of PCB manufacturing?
   A: The panel size can impact the cost of PCB manufacturing in several ways. Larger panel sizes allow for more PCBs to be produced per panel, which can lead to lower unit costs. However, larger panels also require more material and may incur higher tooling and setup costs. Smaller panel sizes may be more cost-effective for low-volume production or when the PCB designs are small. It is important to find the right balance between panel utilization and cost-effectiveness based on your project’s specific requirements.

Conclusion

Understanding standard PCB panel sizes is crucial for anyone involved in PCB design and manufacturing. By choosing the right panel size, you can optimize production efficiency, reduce costs, and ensure compatibility with assembly processes. Consider factors such as PCB design dimensions, production volume, manufacturing capabilities, and assembly requirements when selecting a panel size.

Remember to consult with your PCB manufacturer to discuss your specific needs and obtain their recommendations. They can provide valuable insights based on their experience and equipment capabilities.

By following best practices and utilizing standard panel sizes, you can streamline your PCB manufacturing process, achieve better results, and bring your electronic products to market more efficiently.