Designing Circuit Boards with EAGLE: Make High-Quality PCBs at Low Cost

Chapter 6. Routing

In Chapter 3, “Designing a Simple Circuit,” the op-amp circuit was so simple that its connections could be routed on a single layer. In contrast, the Femtoduino circuit has many more connections and these connections span two layers. Large-scale circuit designs may require thousands of connections and more layers than just the top and bottom. As an example, the BeagleBone Black in Chapter 14, “Schematic Design for the BeagleBone Black,” and Chapter 15, “Board Design for the BeagleBone Black,” requires six layers.

The process of forming these connections between the packages’ pads is called routing, and in my designs, I spend more time routing than in any other activity. If you read reviews of circuit design applications, you’ll ...