After weeks of research and planning as well as waiting for all the parts to be shipped I finally built and finished this amazing project. The aim was to build a power supply without spending a dime... ya that's right this build was free. After quite some time of tinkering with arduino and breadboarding electronics I was getting really annoyed at the lack of options for power and the hassle of unhooking and limited build because of power issues. I then stumbled apon many different versions of the bench top power supply. I noticed however that none of these builds seemed specific for what I was looking for so away I went. I would like to thank all of the suppliers who worked with me and provided the materials needed for this project. Links as well as resources will be included for your own needs.
This power supply is quite handy for many functions. Mine includes three seperate binding posts for different ranges of power such as: +3.3v, +5v, +12v as well as options to expand. Which will be updated as I progress and addon. The cool part of this I believe is in the enclosure itself as it acts as a perfect surface to breadboard as well as operate an ARDUINO or ARDUINO'S lol like I plan.
This project is very easy to do and once built it will allow a cleaner look as well as endless possibilities.
Materials:
- ATX power supply: To provide the power
You can salvage one from an old pc like I did plus you can score extra goodies from dismantling a pc
- Enclosure or box or whatever you plan to use: To enclose your project
I used a enclosure from OKW ENCLOSURES INC. These guys can help out with custom enclosures of all sorts. You can check them out @ http://www.okusa.com/
- Binding Posts: Used for connecting
I lucked out and found a great supplier CHK ELECTRONICS who was eager to help and provided sweet binding posts you can check out the site @ http://www.chk-electronics.com/home.php
- Leds: Used to display standby mode as well as power good mode
I scored yet again and found a great site and company BIVAR LED who was willing to help a brother out you can check it out @ http://www.bivar.com/
- Resistors: I used two 300ohm resistors each one attached to the negative leg of each led. It was all I had in my tackle box
- 12v pc fan: Acts in place of minimum load required to operate atx
I didnt have a 10w sandbar resistor so I figured if the atx needs something to draw minimum current why not just use a fan. This way it doubles as a cooling unit as well as provides the resistance... I could be wrong but it made sense to me.
Salvaged from the pc I killed
- Illuminated Push button: Serves as an on/off
I chose to use an illuminated button for two reasons. One, it looks mint and as well provides a good function to be able to turn source on and off. I was lucky to get a supplier NKK SWITCHES who helps out quite often with my projects. They have a ton of product at great prices. You can check em out @ http://www.nkkswitches.com/products/illuminated-pushbutton/
For this project I also recommend and I mean highly recommend using heat shrink to keep it clean and your wires pretty and protected. As well as a solder iron and basic power tools for cutting out your enclosure. Honestly I didnt have the proper cutting tools and it shows but I plan on covering my mistakes with coolness such as lcd display and possibly usb ports. **DANGER**As always be careful because the ATX unit carries a risk of electrocution and even stores a charge for quite some time even when unplugged so be careful.
I chose to cut up the enclosure and install the hardware and make sure sure everything would fit properly. So trace or make a template that fits your space as well as your needs. I have seen many available to download on the internet so if you need help google it. I used a drill to cut out most of my holes, I also did resort to using a steak knife to cut and my gf's nail tool to sand edges lol. 
So as you can see my holes are not picture perfect but let me defend that by saying I plan to put covers over the rough spots so you wont see em when I am done done. Anyways so for ventilation I made multiple holes in front and back of unit with drill. Again your feel to make your own mess.
Step 2:
ADD HARDWARE
After the holes are to your liking its now time to dress up this power supply. I chose three binding posts because thats all the power I could handle. You may need more. This step is super simple plus feels really satisfying seeing progress.
I installed all the binding posts then didn't like the placement so that's why I had a mess. (which will be fine) Also this is the perfect time for you to install the leds that will be used for showing when the power supply is on and also on standby mode.
After you have everything connected and looking nice we now move on to the best part. Time to play with some wires.
STEP 3:
This step is quite simple as long as you can handle a mess of wires. My advice is to keep it clean and simple. What we will be doing here is cutting all the wires to equal length and sorting by colour. Easy peasy. **DANGER** As I said before be aware of the dangers dont have the unit plugged in and as well discharge it.
This is the atx power supply I used. Check out the specs.
STEP 4:
Now its time to connect the wires to the correct places. So solder the groups of wire together and prepare to add your connectors. Depending on the size of your connectors will depend on the number of wires you can fit. I learned the hard way. After the group of wires are soldered place heat shrink over the wires and attach the connector. Fit the heat shrink to cover the wire as well as connector end and apply heat. Done and done. Next do the same with the grouping of orange wire. As well as red
Okay so before we proceed Ill give you a heads up. Keep in mind of things you would like to add that could affect your wire placement as well as wire count. I chose to add a 12v additional fan. This helps keep enclosure cool as well as a poor mans resistor. I used 1 yellow wire and one ground. So before you bunch all colours togther ask yourself how many do you need/ want. Again I learned the hardway.
Ok so the leds I installed serve two purposes. One they look cool and secondary they act as a standby indicator and a power good check. So it shows when the unit is just turned on as well as when it is in standby mode. In standby mode I believe the white wire provides a steady 5v
LED STANDBY/POWERGOOD/PUSHBUUTON
So with the first led connect the purple wire to the positive end and the negative end connected to negative with a 300ohm resistor in between. this will be the standby mode light. When it is light it is in standby mode.Second led is to let you know that power supply is operating properly and is good. Same thing as before. Negative to negative wire with of course 300ohm resistor. The positive from led goes the the grey wire. I suggest yet again heat shrink and electrical tape. keep it clean. The button I used was easy to install. *Important* In order for the device to run properly the green wire needs to be connected to a ground wire. This is due to the fact the the device is designed to only run if it senses a load. To trick the unit you must connect the green to ground. Because my button is illuminated it required me to connect a 5v wire and ground to it as well as the green and ground. Your button is different so make sure you check your data sheet.
STEP 5:
Now is the fun part. Time to connect the power to the bindings. This is where the connectors come in handy. Makes it very simple to just unscrew bindings and attach the wire group. As you can see from the picture you can find the colour groups here. Mine are as follows:Orange: +3.3v
Black: ground
Red: +5v
Grey: Power ok
Purple: +5v SB
White: -5v
Green: PsON
Blue: -12v
Now its just a matter of attaching to the proper binding posts and you should be read to fire it up.
Enjoy and check back here for upcoming add ons and updates
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