Introduction: ATX Workbench Power Supply Project

About: Computer programmer and electronics tinkerer extraordinaire. Writing coding since the 4th grade(1974). Scuba Dive Master, Eagle Scout.

This instructable will show you how to make a professional looking bench power supply. A power supply that is fuse linked. A power supply that if and when the ATX power supply goes bad you can just unplug and replace it.

Step 1: Parts Needed

Step 2: Install Parts in Case.

Install all binding posts, fuse holders and switch.

Hot glue LED holder and LED in place.

Cut and strip 6 (18ga) wires 2-3/4” (5 red – 1 black).

Solder wires to the fuse holders.

Solder wires to the binding posts.

Purchase/Harvest ATX power supply and 20/24 pin ATX power supply extension.
(NOTE: The wire colors do not always match)

Cut off MALE side of extension and strip ALL Wires 3/8”
(NOTE: The wire colors do not always match)
it’s best to refer to the wires by PIN NUMBER (see chart)

Step 3: Cut and Pair Wires

Pair up wires for soldering.

Solder and heat shrink the ends.

Connect the ATX power supply.

Install screws for the ATX power supply.

Double check wire clearance (Pinched wires are no fun).

Attach rubber stick-on feet to bottom corners.

Step 4: ATX Plug Breakout

Wire Position Chart

Step 5: Step by Step

Steps to follow

Step #1 Install binding posts, fuse holders, toggle switch and LED(hot glue in place) as shown in figure 5

Step #2 Cut wire (18 ga) 2-3/4” long, 5-red / 1-black, strip and solder to fuse holders and to bindings as shown in figure 6, 7 & 8

Step #3 Cut MALE end off the ATX extension and strip ALL wires as show in figure 10

Step #4 Pair up wires for soldering as show in figure 11 (follow the above WIRE PAIRING CHART)

Step #5 Solder the wires to the fuse folders, toggle switch and LED as shown in figure 12

  • #5-a Solder 10 watt power resistor to PIN 3(COM/BLACK) and 4(+5VDC RED) – This creates a load on the power supply
  • #5-b Solder PIN 5, 15, 16 & 17(COM/BLACK) together on fuse holder for BLACK binding post(COM/GND)
  • #5-c Solder PIN 1, 2 & 11(ORANGE & BROWN WIRES) together on fuse holder for GREEN binding post (+3.3VDC)
  • #5-d Solder PIN 19, 20 & 6(+5VDC/RED) together on fuse holder for RED binding post (+5VDC)
  • #5-d Solder PIN 10 (+12VDC/YELLOW) on fuse holder for YELLOW binding post(+12VDC)
  • #5-e Solder PIN 12 (-12VDC/BLUE) on fuse holder for BLUE binding post(-12VDC)
  • #5-f Solder PIN 18 (-12VDC/WHITE) on fuse holder for WHITE binding post(-5VDC)
  • #5-g Solder PIN 7 (COM/BLACK) to 330 ohm resistor and then to CATHODE (-)side of LED (SHORTEST)
  • #5-h Solder PIN 8 (POK/GRAY) to ANODE (+)side of LED (LONGEST)
  • #5-i Solder PIN 13 (COM/BLACK) to center post of toggle switch
  • #5-j Solder PIN 14 (PS-ON/GREEN) to lower post of toggle switch (so toggle down position is OFF)

Step #6 PIN 9 (+5VSB/PURPLE) NOT USED – Cover with heat shrink tubing

Step 6: Final Assembly and Label

Install the cover.

Install cover screws (#6 or #8 pan head 1/4”).

Add a label for voltages and power switch on/off.

The voltage label was made using a Brother P-Touch label maker.
“3.3V(6 spaces)5V(6)12V(6)-5V(4)-12V(5)GND(2)OFF”

Trim the left side of the 3.3V and right of GND on each side to fit.

Attached is a PDF with all the steps and links.


Hope you enjoyed this instructable.

Cheers,
Jeff