Introduction: LED Pacman Ghosts

By NextFab
About: Collaborative workspace with digital and traditional fabrication tools, 3D printers, CNC machines, classes, events, and professional consulting services.

Make your own LED Pacman Ghosts! Feel free to customize your own with colors or add more LEDs. Works well as a desk toy or even a nightlight!

Step 1: Setup

What you'll need:

Tools:

  1. Laser cutter
  2. Hot glue gun
  3. Soldering iron
  4. Computer
  5. Wire cutters
  6. Wire strippers

Components

  1. Acrylic (color of your ghost)
  2. Arduino Uno
  3. (16) 10mm LEDs (color of your ghost)
  4. (4) 10mm white LEDs
  5. (4) 180 Ohm resistors

Step 2: Laser-cut Ghost

Download our designed Pacman ghost cutouts or make your own! The Adobe Illustrator files are available here for download.

Attachments

Step 3: Place in LEDs

The easiest way to do this is to clamp your acrylic in a vice and drop in your LEDs from the back while you continue the build.

Step 4: Hot Glue

After placing the LEDs in the holes, it is necessary to hot glue the side of each LED to the back of the acrylic so the stay in permanently.

Step 5: Solder

For this part, we are going to solder some common anodes. After some testing with the Arduino, I found that the most a digital pin can power without losing much brightness is 8 10mm LEDs in parallel. Since we have 16 red LEDs here, I soldered a common anode (the longer lead) for the 8 LEDs on the left side and then a common anode for the 8 on the right side. For the white LEDs, I soldered together the anodes of the first and third LEDs and the anodes of the second and fourth LEDs. The cathodes of each LED can be left pointing outward. Solder a jumper wire to each set of connected LEDs (there should be 4 total) anywhere along the common anode for each set (see picture 4)

Note: Look at the fourth picture to see the proper soldering for the white LEDs, the other pictures show an attempt that do not work with this code! The first and third white LEDs should be sharing a common anode and the second and fourth should share one. The originals show one and two sharing an anode and three and four sharing an anode - this will not work!

Step 6: Hot Glue Again

Hope you didn't put away your glue gun just yet! After soldering the anodes of the LEDs, hit the base of each LED with a glob of glue just to ensure the anode and cathode stay separated and don't short!

Step 7: Breadboard

The wiring for this project is quite simple and can be done fairly easily with some analog circuitry - but with the Arudino you can easily go back and change the functionality and make this project even cooler, so why not use one?

  1. Grab your 20 wire ribbon cable and attach the female end of each wire to the cathode of each LED. From there, take the male ends and plug them all into a ground rail, and take a jumper from that rail and plug into the GND pin on your Arduino.
  2. Run a jumper wire from pin 2 onto the breadboard, connect it to a 180 ohm resistor, and connect that to the jumper coming from the anode of the LEDs on the right side of your ghost.
  3. Run a jumper wire from pin 5 onto the breadboard, connect it to a 180 ohm resistor, and connect that to the jumper coming from the anode of the LEDs on the left side of your ghost.
  4. Run a jumper wire from pin 3 onto the breadboard, connect it to a 180 ohm resistor, and connect that to the jumper coming from the anode of the one of the pairs of white LEDs (either pair will work)
  5. Run a jumper wire from pin 4 onto the breadboard, connect it to a 180 ohm resistor, and connect that to the jumper coming from the anode of the other pair of white LEDs

Step 8: Arduino Coding

Attached is the code used to power these ghosts. Feel free to play with it and make them even cooler!

Attachments