Building electronics with Arduinos, motors and other gadgets, I came up against a common problem: powering the circuits with a consistent voltage and adequate current. Like many people, I realized that a computer power supply can be a perfect solution, albeit with some modifications. It provides regulated 3.3V, 5V and 12V power at a current level high enough to satisfy almost any project requirement.
Most of the examples I found online did not fit my requirements, so I decided to modify my own. The requirements I set out were:
- ability to switch 24 pin ATX connector for other projects
- variety of connectors
- ample power
Bill of Materials
1x 300W power supply with a rear fan - $30 - Newegg
1x Cytron ATX Power supply breakout board - $9 - Robotshop
1x Power distribution block - $2 - Adafruit
5x 2.1mm DC barrel jack connectors - $5 - Various
5x 5mmx20mm fuse holders - $5 - Various
4x M3 brass standoffs
5x 5mmx20mm fuses (assorted of 5A, 3A, 1A) - $10 - Various
5x 5mm screw terminal pairs - $2 - Various
Assorted drill bits
Step drill with 3/16", 3/8" and 1/2" sizes
The core component that makes this project easy is the ATX breakout board. It takes a 24 pin ATX power cable and splits the components out to their different voltages, while also providing indicator lights, an ON/OFF switch, and room for screw terminals.
Be sure to properly research the power supply: you'll need to select one with a full 24 pin ATX power cable, rear fan instead of the top and enough connectors for your project. If you decide to copy my barrel jack configuration, you'll be using 1 4 pin Molex and 1 SATA cable.
Please remember that a computer PSU provides a dangerous amount of power and has a warranty sticker on it. Since this is a hacking contest and website, I'm sure this won't deter many people. Just be smart.