Understanding Gerber Files for PCB Fabrication

Gerber files are the standard file format used in the PCB industry to describe the printed circuit board design for manufacturing. They contain all the necessary information for PCB fabrication, including the copper layers, solder mask, silkscreen, and drill data. When submitting your PCB design to a manufacturer like RAY PCB, it’s essential to provide the correct Gerber files to ensure accurate and efficient production.

What are Gerber Files?

Gerber files, also known as Gerber format or RS-274X format, were developed by the Gerber Systems Corp. in the 1960s. They have since become the de facto standard for the PCB industry. Gerber files are ASCII text files that describe the geometric and layer information of a PCB design using a series of commands and coordinates.

Each Gerber file represents a specific layer or aspect of the PCB, such as:

• Copper layers (top, bottom, and inner layers)
• Solder mask (top and bottom)
• Silkscreen (top and bottom)
• Solder paste (top and bottom)
• Drill data (plated and non-plated holes)

Advantages of Using Gerber Files

Using Gerber files for PCB fabrication offers several advantages:

1. Universality: Gerber files are widely accepted by PCB Manufacturers worldwide, making it easy to switch suppliers or get quotes from multiple sources.

2. Simplicity: Gerber files are simple ASCII text files that can be easily viewed, edited, and manipulated using various software tools.

3. Reliability: Gerber files provide a reliable and accurate representation of the PCB design, reducing the chances of errors or misinterpretations during manufacturing.

4. Compatibility: Most PCB design software can export Gerber files, ensuring compatibility with different manufacturing processes and equipment.

Gerber Files Supported by RAY PCB

RAY PCB supports a wide range of Gerber files to cater to the diverse needs of their customers. The following table lists the Gerber file types supported by RAY PCB:

Gerber File Type	Description
.GBL	Bottom copper layer
.GBO	Bottom silk screen
.GBS	Bottom solder mask
.GBP	Bottom solder paste
.GTL	Top copper layer
.GTO	Top silk screen
.GTS	Top solder mask
.GTP	Top solder paste
.G1, .G2, …, .Gn	Inner copper layers (n = layer number)
.GKO	Board outline
.GM1, .GM2, …, .GMn	Mechanical layers (n = layer number)
.TXT	Drill data (Excellon format)
.DRL	Drill data (Excellon format)

Copper Layers

Copper layers are the conductive paths that interconnect the components on the PCB. RAY PCB supports the following copper layer Gerber files:

• .GTL: Top copper layer
• .GBL: Bottom copper layer
• .G1, .G2, …, .Gn: Inner copper layers (n = layer number)

Solder Mask

Solder mask is a protective coating applied over the copper layers to prevent accidental short circuits and improve the PCB’s appearance. RAY PCB supports the following solder mask Gerber files:

• .GTS: Top solder mask
• .GBS: Bottom solder mask

Silkscreen

Silkscreen is the text and graphics printed on the PCB’s surface for component identification, branding, and assembly instructions. RAY PCB supports the following silkscreen Gerber files:

• .GTO: Top silkscreen
• .GBO: Bottom silkscreen

Solder Paste

Solder paste is a mixture of tiny solder particles and flux used in the surface mount assembly process. RAY PCB supports the following solder paste Gerber files:

• .GTP: Top solder paste
• .GBP: Bottom solder paste

Mechanical Layers

Mechanical layers contain non-electrical information such as board outline, dimensions, and fabrication notes. RAY PCB supports the following mechanical layer Gerber files:

• .GKO: Board outline
• .GM1, .GM2, …, .GMn: Mechanical layers (n = layer number)

Drill Data

Drill data specifies the location, size, and type of holes to be drilled in the PCB. RAY PCB supports drill data in the Excellon format, with the following file extensions:

• .TXT: Drill data
• .DRL: Drill data

Preparing Gerber Files for RAY PCB

When preparing your Gerber files for submission to RAY PCB, follow these guidelines to ensure a smooth and error-free manufacturing process:

1. Use a reliable PCB design software that can generate industry-standard Gerber files, such as Altium Designer, KiCad, Eagle, or OrCAD.

2. Ensure that your design adheres to RAY PCB’s design guidelines, including minimum trace width, clearance, and hole size.

3. Generate separate Gerber files for each layer or aspect of the PCB, as listed in the table above.

4. Use a consistent naming convention for your Gerber files to avoid confusion and errors.

5. Include a readme file or fabrication drawing that provides additional information about your PCB, such as layer stackup, material specifications, and special instructions.

6. Compress all your Gerber files and supporting documents into a single ZIP archive before submitting them to RAY PCB.

FAQ

1. What is the difference between Gerber files and ODB++ files?

2. Gerber files are the traditional standard for PCB fabrication, representing each layer or aspect of the PCB as a separate file. ODB++ (Open Database++) is a newer, more comprehensive format that stores all the PCB design data in a single database file. While RAY PCB supports both formats, Gerber files are more widely used and accepted in the industry.

3. Can I submit my PCB design to RAY PCB in a format other than Gerber?

4. Yes, RAY PCB also accepts PCB designs in ODB++ format. However, Gerber files are the most common and preferred format for PCB fabrication.

5. What if I’m missing some of the Gerber files listed in the table?

6. The specific Gerber files required for your PCB may vary depending on its complexity and design requirements. At a minimum, you should provide the copper layer files (.GTL, .GBL, and inner layers if applicable), solder mask files (.GTS and .GBS), and drill data (.TXT or .DRL). If your PCB has silkscreen, solder paste, or mechanical layers, include those files as well.

7. How do I ensure that my Gerber files are correctly generated?

8. Most PCB design software have built-in Gerber file generation tools that automatically create industry-standard Gerber files. However, it’s essential to double-check your settings and review the generated files using a Gerber viewer to ensure accuracy and completeness. RAY PCB also offers a free Gerber file review service to help identify any issues before proceeding with manufacturing.

9. What should I do if I encounter issues or have questions about submitting Gerber files to RAY PCB?

10. If you have any questions, concerns, or issues related to submitting Gerber files to RAY PCB, don’t hesitate to reach out to their customer support team. They have experienced engineers and technicians who can guide you through the process, review your files, and provide assistance to ensure a successful PCB fabrication experience.

Conclusion

Gerber files are the backbone of the PCB fabrication process, providing a standardized and reliable way to communicate PCB design data to manufacturers like RAY PCB. By understanding the different Gerber file types supported by RAY PCB and following the guidelines for preparing and submitting your files, you can streamline your PCB fabrication experience and ensure high-quality results.

Remember to generate separate Gerber files for each layer or aspect of your PCB, use a consistent naming convention, and include all necessary supporting documents. If you encounter any issues or have questions along the way, don’t hesitate to reach out to RAY PCB’s customer support team for assistance.

By leveraging the expertise and capabilities of RAY PCB and providing accurate, complete Gerber files, you can bring your PCB designs to life with confidence and reliability.