What is EAGLE?

EAGLE is a PCB design software developed by Autodesk. It consists of a schematic editor, a PCB layout editor, and a library of electronic components. EAGLE allows users to design electronic circuits and create PCB layouts for manufacturing.

Getting Started with EAGLE

To get started with EAGLE, you need to download and install the software on your computer. Autodesk offers a free version of EAGLE for non-commercial use, which includes all the essential features for designing schematics and layouts.

Creating a New Project

1. Launch EAGLE and click on “File” > “New” > “Project”.
2. Choose a location to save your project and give it a name.
3. Click “OK” to create the project.

Creating a Schematic

1. In the EAGLE Control Panel, right-click on your project and select “New” > “Schematic”.
2. A new schematic editor window will open.
3. Use the “Add” tool to place components from the libraries onto the schematic.
4. Use the “Net” tool to connect the components with wires.
5. Use the “Name” tool to assign names to the nets and components.
6. Save your schematic by clicking on “File” > “Save”.

Creating a Layout

1. In the schematic editor, click on “File” > “Switch to Board”.
2. EAGLE will create a new board file and open the layout editor.
3. Use the “Move” tool to arrange the components on the board.
4. Use the “Route” tool to create traces between the components.
5. Use the “Via” tool to create connections between different layers of the board.
6. Use the “Polygon” tool to create copper fills for ground planes or power planes.
7. Save your layout by clicking on “File” > “Save”.

EAGLE Libraries

EAGLE comes with a large library of electronic components, including resistors, capacitors, ICs, connectors, and more. These libraries contain both schematic symbols and PCB footprints for each component.

Using Existing Libraries

1. In the schematic or layout editor, click on the “Add” tool.
2. In the “Libraries” tab, browse through the available libraries and select the desired component.
3. Click “OK” to place the component on the schematic or layout.

Creating Custom Libraries

If you can’t find a specific component in the existing libraries, you can create your own custom library.

1. In the EAGLE Control Panel, click on “File” > “New” > “Library”.
2. Create a new schematic symbol using the drawing tools.
3. Create a new package (PCB footprint) for the component.
4. Assign the schematic symbol to the package.
5. Save the library and use it in your projects.

Design Rules and DRC

EAGLE includes a Design Rule Check (DRC) feature that helps ensure your PCB layout meets the manufacturing requirements. Design rules define the minimum clearances, trace widths, drill sizes, and other parameters for your PCB.

Setting Design Rules

1. In the layout editor, click on “Tools” > “DRC”.
2. In the DRC dialog, select the appropriate design rules for your PCB manufacturer.
3. Click “Check” to run the DRC and view any violations.
4. Fix the violations by adjusting the layout or modifying the design rules.

Common Design Rules

Parameter	Typical Value
Minimum trace width	0.2 mm
Minimum trace spacing	0.2 mm
Minimum drill size	0.3 mm
Minimum annular ring	0.15 mm

Generating Manufacturing Files

Once your PCB layout is complete and passes the DRC, you can generate the necessary files for manufacturing.

Gerber Files

Gerber files are the industry standard for PCB fabrication. They contain the information needed to manufacture the PCB, including the copper layers, solder mask, and silk screen.

1. In the layout editor, click on “File” > “CAM Processor”.
2. In the CAM Processor, select the “gerber274x.cam” job.
3. Click “Process Job” to generate the Gerber files.

Drill Files

Drill files contain the information needed to drill holes in the PCB for through-hole components and vias.

1. In the CAM Processor, select the “excellon.cam” job.
2. Click “Process Job” to generate the drill files.

Bill of Materials (BOM)

A bill of materials (BOM) is a list of all the components used in your design, including their quantities, part numbers, and descriptions.

1. In the schematic editor, click on “File” > “Export”.
2. Select “BOM” as the export format.
3. Choose the desired options and click “OK” to generate the BOM file.

Tips and Tricks

• Use a consistent naming convention for your components and nets to keep your schematic organized.
• Create a ground symbol in your schematic and connect all ground points to it.
• Use the “Group” tool to move multiple components or traces at once in the layout editor.
• Use the “Ratsnest” tool to view the shortest possible connections between components in the layout editor.
• Use the “Autorouter” tool sparingly, as it may not always produce the most optimal layout.

Frequently Asked Questions (FAQ)

1. What is the difference between a schematic and a layout in EAGLE?

2. A schematic is a graphical representation of an electronic circuit, showing the components and their connections. A layout is the physical arrangement of the components and traces on a PCB.

3. Can I use EAGLE for free?

4. Yes, Autodesk offers a free version of EAGLE for non-commercial use. It includes all the essential features for designing schematics and layouts.

5. How do I create a custom footprint in EAGLE?

6. To create a custom footprint, you need to create a new package in a library. Use the drawing tools to define the pad sizes, shapes, and positions, as well as any silkscreen or keepout areas.

7. What are the different layers in an Eagle PCB layout?

8. EAGLE PCB layouts typically include copper layers (Top, Bottom, and Inner), solder mask layers (tStop and bStop), silkscreen layers (tPlace and bPlace), and drill layers (Drills and Holes).

9. How do I export my PCB layout for manufacturing?

10. To export your PCB layout for manufacturing, use the CAM Processor in EAGLE to generate Gerber files and drill files. These files can be sent to a PCB manufacturer for fabrication.

Conclusion

EAGLE is a powerful and versatile PCB design software that allows you to create professional-grade schematics and layouts. By following the basic steps outlined in this article, you can start designing your own custom PCBs using EAGLE. Remember to use consistent naming conventions, follow design rules, and generate the necessary manufacturing files for your PCB. With practice and experience, you can master the art of PCB design using EAGLE.