A beginning tutorial to Eagle PCB Schematic Editor

By Azhar Jaffar

First open a new Schematic

Next add a new part using the icon on the toolbar

Go ahead and use the search field to find the Ground symbol. Double click on the GND under supply1 to

select that part

Left-click and place the part somewhere.

Do the same with Vcc and choose the one under supply1. You can use the zoom toolbar to navigate

around the circuit. Click on the left one to auto center the schematic

Next add a capacitor. Let’s select a 1uF surface mount capacitor. The normal package for this value is the

1812, pick this one

After placing the capacitor lets start connecting the components together. We use the NET tool to

connect the GND to the capacitor. Left click to start the wire and double click to end the wire.

After connecting the wires we need to place junctions at where the wire connects to the part. Don’t

forget these; they are important to make the connections

Next add a header. The part name is MA04-1

And a MAX233 serial line converter

And add the Serial connector. Part is listed as F09HP

Your schematic should now look something like this

.

To make the serial port connection to most devices we need to loop-back a couple of signals. Make

these connections. 1, 4, 6 shorted together. And 7 and 8 shorted together.

Notice that you can change the way lines are drawn by using the right mouse button. Also don’t forget

the Junctions.

Next we need to configure the MAX233 chip to run the way we want. Short together the C2+ then the

C2- and the V-. Leave the rest un-connected. Read the datasheet on the part for more information if you

are interested.

Now let’s wire up the header so our chip can get power. Remember in the first step selecting the GND

and VCC parts. This allows us to connect power to any chips that need power. Notice in the MAX233

part there are no provisions to connect ground and Vcc to it.

Now we are almost done with the schematic. Just make the rest of the connections as shown. Don’t

forget pin 5 on the serial port to ground.

Now that the schematic is finished, click on the board icon to start working on the board Click on Yes

Then you should have something like this

Let do some moving around of the parts so that they are placed better. Use the button to move

parts around. Left click to pickup and putdown a part. Use the right click to rotate the part.

Play around with the placement to get something that is a little smaller. Try to get it so that not too

many signals cross each other. This will lead to an easer routing job.

Now that we have finished placing the parts for now try the default auto route by clicking on the

icon of the left side. This screen will pop up; just hit ok accepting all the default values After

hitting ok you should see a routed board that looks something like this.

After hitting ok you should see a routed board that looks something like this.

Looking at the board we may or may not like what the auto router has done. We can use the rip-up and

Route tool to do our own placement. Play around with the tool and see if you can do better

than the auto router.

After playing around with the routing tool for a bit lets try to change some of the auto routing settings.

But to start over we need to rip-up all the traces. Use the tool to select the entire circuit. Then

select the rip-up tool and right click to rip-up everything that is selected.

Now it should be back to where we were before running the auto routing tool.

Select the DRC icon .

Go to Sizes and change the Minimum Width to 20mil instead of the default 10. Hit OK then rerun the

auto-router with the default settings again.

Notice the Wider traces. This is because we changed the Rule file to say that the minimum width is

20mil. The auto router will obey these rules and will make no traces smaller than this.

Go ahead and play around with all the settings and try to get something you like. For example fatten up

the power and ground wires. Have fun!

When you have finished this tutorial be sure to save the .sch and the .brd files for use later on.