Turn Your EAGLE Schematic Into a PCB

Turn Your EAGLE Schematic Into a PCB

I guess I should say that we’ll make a PCB DESIGN; making the physical board is a different task, and there are a lot of tutorials on the net (and even some instructables) on making the board after you have the design.

Cadsoft EAGLE generic information:Cadsoft is a German company that is a veritable mecca of software distribution enlightenment. In addition to the reasonably priced professional PCB design packages ($1200), they have freeware, lite, non profit, and other intermediate licenses. Their software runs under windows, linux, and MacOSX. It’s slightly quirky, with a steep (but not too high) learning curve on the front end, but from most reports it is not any more so than other professional CAD packages. They have online support forums that are active from both the company and other users, the package is under current development and gets better with each release. A number of PCB fabricators will accept their CAD files directly. It’s good stuff.

Use it. Propagate it. Buy it when you “go pro.”

Step 1: Starting From the Schematic.

So this is the schematic we have from the Schematic Instructable. Up in the file menu, there’s a “Switch to board” selection. ROUTE is for drawing copper.)VIA create a hole and pad associated with some signal.

I’ll describe the remaining icons toward the end,
Turn Your EAGLE Schematic Into a PCB
and assign them “useful” or “useless.”Step 3: The Untouched PCB Design

This is what the newly created board design will look like. All your components will be in a clump over to the left of the origin, and there will be a frame that marks the allowed size of a board when using the freeware or “Lite” versions of EAGLE (80x100mm). All the component pads will have to be inside that outline when you move them around, although you can cheat a bit and have traces or board outlines that exceed the board size limit. This has the annoying side effect that if you pick up a component from it’s original localtion, you can’t put it back down outside the outline (however, you can use ESC to abort the move, and the component will revert to its original location.) Ok, a few defintions are in orderAll the signals you created in the schematic are currently AIR WIRES; thin yellow lines that are drawn in the shortest possible way, crossing each other as needed. They stay connected to component pins even when you move the component around. The RATSNEST command recomputes and redraws these after you move things around (and, say, make two connected pins closer together than they used to be.)ROUTING a signal consists of turning an airwire into an actual copper trace on some layer(s) of the board, and positioning that trace so that it doesn’t short agains other traces on the same layer of the board. The Freeware version of Eagle only supports a TOP and BOTTOM layer, and as hobbyists we have motivation to try to use only ONE layer. A confusing multitude of layers. Most of the drawing commands have a layer selection pulldown menu that you can use for specifying which layer you want to draw on (exceptions include objects like vias that span multiple layers.)Here are some of the more important layers:Step 5: Move the Components Into the Legal Area

The first thing we want to do is move at least some components into the legal board area where we can work with them. If you have a particularly large board with many components,
Turn Your EAGLE Schematic Into a PCB
you might want to do this a section at a time. Then select the MOVE icon and RIGHT click (right clicking selects the group instead of a single component) and drag the set into the board outline.