Creating Fabrication and Assembly Drawings in Altium Designer

Introduction

Altium Designer is a powerful electronic design automation (EDA) software suite that provides a comprehensive set of tools for designing and documenting printed circuit boards (PCBs). One of the essential features of Altium Designer is the ability to create fabrication and assembly drawings, which are critical for the manufacturing process of PCBs. These drawings provide detailed instructions and specifications for the fabrication and assembly of the PCB, ensuring that the final product meets the design requirements.

In this article, we will explore the process of creating fabrication and assembly drawings in Altium Designer. We will cover the following topics:

Table of Contents

1. Understanding Fabrication and Assembly Drawings
2. Preparing for Fabrication and Assembly Drawing Creation
3. Creating Fabrication Drawings
   • Generating Gerber Files
   • Creating Drill Drawings
   • Creating Solder Mask Drawings
   • Creating Silkscreen Drawings
4. Creating Assembly Drawings
   • Creating Component Overlay Drawings
   • Creating Pick-and-Place Files
5. Finalizing and Outputting Drawings
6. FAQ

Understanding Fabrication and Assembly Drawings

Before we dive into the process of creating fabrication and assembly drawings, it's essential to understand their purpose and the different types of drawings involved.

Fabrication Drawings

Fabrication drawings, also known as manufacturing drawings or documentation, provide detailed instructions and specifications for the fabrication of the PCB. These drawings include:

• Gerber Files: Gerber files are a standard file format used in the PCB industry to represent the physical layout of the PCB. They contain information about the copper layers, solder mask, silkscreen, and other critical aspects of the PCB design.
• Drill Drawings: Drill drawings specify the locations and sizes of the holes that need to be drilled in the PCB for components, vias, and other features.
• Solder Mask Drawings: Solder mask drawings define the areas of the PCB that will be covered by a protective solder mask layer, which prevents solder bridges and shorts during the assembly process.
• Silkscreen Drawings: Silkscreen drawings provide instructions for printing text, logos, and other markings on the PCB's surface, typically for component identification and assembly guidance.

Assembly Drawings

Assembly drawings, on the other hand, provide instructions and information for the assembly of components onto the fabricated PCB. These drawings include:

• Component Overlay Drawings: Component overlay drawings show the locations and orientations of components on the PCB, making it easier for assembly operators to place the components correctly.
• Pick-and-Place Files: Pick-and-Place files are used in automated assembly processes, providing instructions for pick-and-place machines to accurately place components on the PCB.

Preparing for Fabrication and Assembly Drawing Creation

Before creating fabrication and assembly drawings, it's crucial to ensure that your PCB design is complete and error-free. Here are some preparatory steps:

1. Design Rule Check (DRC): Run a comprehensive design rule check to identify and resolve any potential issues in your PCB design, such as clearance violations, short circuits, or unconnected nets.
2. Electrical Rule Check (ERC): Perform an electrical rule check to verify the electrical integrity of your design, including proper connectivity, power and ground connections, and compliance with design specifications.
3. 3D Clearance Check: If your design includes components with complex shapes or enclosures, perform a 3D clearance check to ensure there are no mechanical interference issues.
4. Back-Annotation: If you've made any changes to the PCB design after the initial schematic capture, back-annotate the schematic to ensure consistency between the schematic and PCB layout.

Creating Fabrication Drawings

Generating Gerber Files

Gerber files are the industry-standard format for representing the physical layout of a PCB. They are used by PCB fabrication houses to produce the actual PCB. To generate Gerber files in Altium Designer, follow these steps:

1. Open your PCB design in Altium Designer.
2. Go to "File" > "Fabrication Outputs" > "Gerber Files..."
3. In the Gerber Files dialog box, select the layers you want to include in the Gerber files. Typically, you'll need to include the following layers:
   • Top Copper Layer
   • Bottom Copper Layer
   • Internal Copper Layers (if applicable)
   • Solder Mask Top
   • Solder Mask Bottom
   • Silkscreen Top
   • Silkscreen Bottom
4. Configure the output settings according to your requirements or the specifications provided by the fabrication house.
5. Click "OK" to generate the Gerber files.

Altium Designer will generate a set of Gerber files, one for each layer you selected, in the specified output folder.

Creating Drill Drawings

Drill drawings provide instructions for drilling holes in the PCB for components, vias, and other features. To create drill drawings in Altium Designer, follow these steps:

1. Open your PCB design in Altium Designer.
2. Go to "File" > "Fabrication Outputs" > "Drill Drawings..."
3. In the Drill Drawings dialog box, configure the output settings according to your requirements or the specifications provided by the fabrication house. Some common options include:
   • Drill file format (e.g., Excellon, Sieb & Meyer, etc.)
   • Drill units (e.g., inches or millimeters)
   • Drill tool list
   • Drill symbol options
4. Click "OK" to generate the drill drawings.

Altium Designer will generate the drill files in the specified output folder.

Creating Solder Mask Drawings

Solder mask drawings define the areas of the PCB that will be covered by a protective solder mask layer. To create solder mask drawings in Altium Designer, follow these steps:

1. Open your PCB design in Altium Designer.
2. Go to "File" > "Fabrication Outputs" > "Solder Mask..."
3. In the Solder Mask dialog box, configure the output settings according to your requirements or the specifications provided by the fabrication house. Some common options include:
   • Solder mask layer (e.g., Top or Bottom)
   • Output file format (e.g., Gerber, ODB++, etc.)
   • Solder mask expansion settings
4. Click "OK" to generate the solder mask drawings.

Altium Designer will generate the solder mask files in the specified output folder.

Creating Silkscreen Drawings

Silkscreen drawings provide instructions for printing text, logos, and other markings on the PCB's surface. To create silkscreen drawings in Altium Designer, follow these steps:

1. Open your PCB design in Altium Designer.
2. Go to "File" > "Fabrication Outputs" > "Silk-Screen..."
3. In the Silk-Screen dialog box, configure the output settings according to your requirements or the specifications provided by the fabrication house. Some common options include:
   • Silkscreen layer (e.g., Top or Bottom)
   • Output file format (e.g., Gerber, ODB++, etc.)
   • Silkscreen line width and text size
4. Click "OK" to generate the silkscreen drawings.

Altium Designer will generate the silkscreen files in the specified output folder.

Creating Assembly Drawings

Creating Component Overlay Drawings

Component overlay drawings show the locations and orientations of components on the PCB, making it easier for assembly operators to place the components correctly. To create component overlay drawings in Altium Designer, follow these steps:

1. Open your PCB design in Altium Designer.
2. Go to "File" > "Assembly Outputs" > "Component Overlay..."
3. In the Component Overlay dialog box, configure the output settings according to your requirements or the specifications provided by the assembly house. Some common options include:
   • Output file format (e.g., PDF, DXF, DWG, etc.)
   • Component overlay layer (e.g., Top or Bottom)
   • Component annotation options (e.g., reference designators, values, etc.)
   • Board outline options
4. Click "OK" to generate the component overlay drawings.

Altium Designer will generate the component overlay files in the specified output folder.

Creating Pick-and-Place Files

Pick-and-Place files are used in automated assembly processes, providing instructions for pick-and-place machines to accurately place components on the PCB. To create pick-and-place files in Altium Designer, follow these steps:

1. Open your PCB design in Altium Designer.
2. Go to "File" > "Assembly Outputs" > "Pick and Place..."
3. In the Pick and Place dialog box, configure the output settings according to your requirements or the specifications provided by the assembly house. Some common options include:
   • Output file format (e.g., CSV, TXT, IPC-356, etc.)
   • Component pick-and-place order
   • Component rotation and mirroring options
   • Component extraction filters (e.g., include/exclude certain components)
4. Click "OK" to generate the pick-and-place files.

Altium Designer will generate the pick-and-place files in the specified output folder.

Finalizing and Outputting Drawings

After creating the necessary fabrication and assembly drawings, it's important to review and finalize them before sending them to the fabrication and assembly houses. Here are some final steps:

1. Review and Validate: Carefully review all the generated drawings and files to ensure they are complete and accurate. Double-check the output settings and specifications to ensure they match the requirements of the fabrication and assembly houses.
2. Create Zip or PDF Package: Organize all the necessary files into a single zip or PDF package for easy distribution and archiving.
3. Include Additional Documentation: If required, include any additional documentation or instructions specific to your design or project.
4. Submit to Fabrication and Assembly Houses: Submit the finalized package to the respective fabrication and assembly houses, following their preferred submission process (e.g., secure file transfer, online portal, etc.).

By following these steps, you can ensure that your PCB design is accurately translated into fabrication and assembly drawings, enabling a smooth and efficient manufacturing process.

FAQ

1. Q: Why are fabrication and assembly drawings important? A: Fabrication and assembly drawings provide critical instructions and specifications for the manufacturing of PCBs. They ensure that the fabrication house and assembly house have all the necessary information to accurately produce and assemble the PCB according to the design requirements.
2. Q: What is the difference between Gerber files and ODB++ files? A: Gerber files are a widely used industry standard for representing the physical layout of PCBs. ODB++ (Open Data Base Plus Plus) is a more comprehensive and intelligent data format that includes not only the PCB layout but also additional design data, such as component information, design rules, and electrical connectivity.
3. Q: Can I create fabrication and assembly drawings for multiple PCB designs at once? A: Yes, Altium Designer supports batch operations for generating fabrication and assembly outputs. You can select multiple PCB designs and generate the necessary drawings and files in a single operation.
4. Q: How do I ensure that my fabrication and assembly drawings comply with industry standards? A: Altium Designer provides various configuration options and settings to ensure compliance with industry standards, such as IPC (Association Connecting Electronics Industries) standards. Additionally, many fabrication and assembly houses provide specific requirements or templates that you can follow.
5. Q: Can I customize the appearance and content of my fabrication and assembly drawings? A: Yes, Altium Designer offers a range of customization options for fabrication and assembly outputs. You can adjust settings such as layer colors, text sizes, line widths, and component annotations to suit your preferences or meet specific requirements.

By following the steps outlined in this article, you can create accurate and comprehensive fabrication and assembly drawings for your PCB designs using Altium Designer. These drawings are essential for successful manufacturing and assembly, ensuring that your designs are translated into physical products that meet your specifications and requirements.