Motion sensing LED PCB design


  • Designing of a complex circuitry
  • Introduction to the default and custom Eagle libraries


For this project, you will need

  1. Autodesk Eagle PCB on your computer

Let’s begin!

1. Expand Project option and right click on Project Tab.

2. Select  ‘Create New Project’. You can name it Proximity_LED circuit.

3. Right click on the New Project you created -> Select New -> Schematic.


Eagle PCB Dashboard


4. The Schematic window will open where we will create the Schematic for our board. But first, we need to specify the libraries we intend to use.

5. Now we need to add one library file to the eagle PCB which can be downloaded here

6. Launch Eagle and click on Option -> Directories -> Libraries tab -> add the path to folder where the library is extracted separated by ‘;’ and click OK.

7. Right click on the newly added library folder -> Select Use all.

8. Click on Library -> Library Manager -> Click -> Available Tab -> Select all shown libraries -> Click Use.


Library manager


9. Click on the Add Part button -> Search for LED in the Prox_sen library -> Click Select and put it anywhere on the drawing sheet three times -> press ESC.

Adding components to sketch


10. Similarly search for RES-0207/10 (Resistor) and ZVN2110A which is a transistor in the search bar and place them on the canvas.

11. Click on the Net icon and make the connections as shown in fig below.

Components Arrangement  and connection


12. Now click on the group toolbar select all and press Ctrl+C to copy and paste the same circuit 8 time as shown in figure below.

Replicated Schematics


13. Again click on the Net and complete the circuit as shown.

Final Schematics


14. We should rename the LED we have put on the canvas to distinguish it between IR LED a Photo Transistor or Glow LED which can be done by clicking on the Name tool-> select the component to name-> click out-> and enter the name as shown below.


Name tool


15. Click on the Board/Scheme Button to automatically create a Board File.

16. Once the Board file is created you will see your components out of the PCB, Just click the move button and drag them to the PCB board in the order of the schematic drawing (You might need to rotate the components to get a proper arrangement) follow the schematic in fig below.


Arrangement on Board File


17. Once done click the Autorouter button and you will end up with a diagram like this.


Application of Auto-router Option


18. Now the wire thickness must be increased for the connections to be manufactured. Minimum thickness of the wire should be atleast 0.5 mm.

19. Click on each wire individually and and select properties -> Click on width -> select a size greater than 0.5 mm.


Wire Properties


There you go!

The final diagram will look like this.


Final Board File ready for printing


Your PCB design is ready. Save the file. Click on Cam Tool -> Select the Gerber Option on Left Panel ->  Click Process Job -> select the location to save

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