If you're like me , you've probably toasted dozens of cheap AC-DC adapters , on my last project , the adapter melted and almost caused a fire when it's wires got shorted out , thats when I realized I need a better DC power supply , decent DC power supplies can get expensive , so I decided to build an ATX power supply , since I had many junk PCs lying around .
ATX power supplies can give up to 30 Amperes of current , 3.3v , 5v , or 12v voltage , and automatically turns off in case of electric short .
Parts list :
- Pentium 4 ATX power supply.
- Red LED.
- Green LED.(Optional)
- Toggle switch .
- 4 Banana connectors .
- 2 100k resistors.
- 2 Flat Push-on connectors.(Optional)
Tools list :
- Metal drill bits 5mm for LEDs and banana jacks , and 10mm for the toggle switch .
- Electric drill.
- Soldering gun.
- Soldering iron.
- Wire cutter.
- Electric tape.
- Paper cutter.
- Screw drivers (or whatever you need to take the ATX power supply apart).
My beloved electric Drill with metal bit |
Steps:
- Open the power supply , and drill holes for 2 LEDs , 4 Banana connectors , and a toggle switch.
How my power supply looked when open |
- All we need from the ATX power supply are 8 wires , they are :
- Green : To turn the ATX power supply ON.
- Purple : Connected to LED to show that the Power Supply is Plugged in .
- Gray : Connected to LED to show that the Power Supply is turned on .
- Yellow : 12v.
- Red : 5v.
- Orange : 3.3v.
- 2 x Black : Ground.
When the Green wire is connected to Ground the Power supply will turn ON.
Connect the Black and Green wires to a Flat push-on connectors , On the Black wire side I connected the Black wire from the power supply board , and a free Black wire to Ground the LEDs.
LEDs:
Am using two LEDs a red and green , the green will turn on when the power supply is plugged in , the red will turn on when the power supply is turned on.
The purple wire will turn on once the power supply is plugged in , so connect :
Purple wire > resistor > Green LED > Ground .
The gray wire will turn when the power supply is turned on :
Gray wire > resistor >Red LED > Ground .
Output and Ground: