Intro: Super Basic Low Profile Power Supply
A common issue I have that I'm sure a lot of other electronics hobbyists have is space or lack thereof. Its hard to be an electronics hobbyist when space is limited because it requires so many tools and things to work, you need a soldering iron, oscilloscope, parts bin, power supply and much more. Sure if you do this professionally making space isn't too hard however for a part-time hobbyist you might find your room slowly being engulfed in circuits.
So to save a tiny yet needed amount of space we are going to take a look at how to make a pretty basic power supply that's mounted inside a parts bin.
Step 1: Parts Needed
Okay so the parts we are going to need are as follows:
- 1x Buck/Boost Power supply (Here)
- 1x Laptop Power Brick (ideally you should recycle an old one) (Here)
- 1x Volt Meter (Here)
- 4x Banana Jack (2 red 2 black) (Here)
- 1x Switch (Here)
- 1x Parts Bin (Here)
As you can see most of the parts used are pretty simple, now you may be thinking that that voltmeter is going to be used to measure the output voltage of the power supply however it's not. The power supply listed actually has a built-in screen that displays output voltage and a bunch of other cool things however we are adding this little voltmeter because it saves even more space and is pretty convenient. Sometimes finding a multimeter to measure voltage is a hassle so having this very basic voltmeter installed on your desk makes it easy to quickly check voltages.
Step 2: The Voltmeter
So this voltmeter has 3 wires coming off of it, the red and black are for power and the third wire (which happens to be white on mine) is used to measure voltage. However, the cool thing about this voltmeter is that we can literally power the voltmeter with the source you're trying to measure (as long as its more than 3 volts).
So I decided to take this route because it makes it a little easier when wiring up, to do this all we need to do is create a solder bridge between the source and positive pin and give it a test.
To test that its working connected the positive pin (which now has the source pin soldered to it) to the positive output of the voltage you are trying to measure and then the ground pin of the voltmeter to the ground output. You should see the little screen light up and display the voltage with a margin of error of around 5 percent.
Step 3: Modding and Mounting
Now to fit everything inside we are going to need to make so mods to the parts pin. We start by cutting a section of the front and back away, this section needs to be as wide and as long as your power supply faceplate so make sure to measure. Now once you've made these cuts the parts bin may feel a little less stable as we have removed some of the support structure however this isn't an issue as when the power supply is installed it acts as a support.
Now we want to take a look at how we are going to make the faceplate. The reason for having a faceplate is because for one it makes everything look nice and secondly it helps keep everything together, the faceplate needs to have a hole for the power supply, power switch, voltmeter and banana jacks and so the easiest way to make one is to 3d print one. An STL file can be found below which is for the faceplate and backplate with all mounting holes however if you don't have a 3d printer let me start off by saying I feel your pain and second that by saying since this is a flat object it definitely doesn't need to be 3d printed, you can use any sturdy material that you can cut into such as cardboard or wood.
Once everything is mounted into the faceplate and backplate we can move onto wiring.
Step 4: Wiring
The wiring for this is very basic, let's start by wiring up the volt mete.
The source and positive in pin get soldered to the top red banana jack and the ground wire gets soldered to the top black banana jack. This is why we have 4 banana jacks, the top two are for measuring voltage and the bottom two are for supplying power, this way we can measure voltage and supply it at the same time (so, for example, we can power a boost converter and measure the output at the same time).
Next, we connect the positive output of the Laptop power brick to the positive input of the power supply and the ground output from the brick the ground input of the power supply with a switch in between to allow us to turn the whole system on and off. Now we can solder the positive output from the power supply to the bottom red banana jack the ground output from the power supply to the bottom black banana jack and that's all the wiring we need to do.
Step 5: Mounting in the Parts Pin
Now we need to glue to faceplate and backplate to a base that fits in the parts bin and then slide it into the parts bin, once you're sure it fits properly with no issues we can start using some glue to reinforce it. Mine was able to stay in place from friction alone however by using some super glue we are able to mount it permanently while also providing structural support that I talked about earlier.
Now we can plug it in a give it a test if everything goes well your power supplies screen should light up.
Step 6: The Probes
Now lastly we need a way to plug in alligator clips and probes so to do this we need to find a pair of alligator clips and cut off one end leaving only one alligator clip per a wire. Then we can solder the corresponding colored wire to the male banana jack and plug it in for a test.
Since we only used banana jacks we can plug the alligator clips into both the top or bottom pair of banana jacks to either supply power or measure voltage.
Step 7: Finished
The power supply is done! Since the power supply takes up two slots on the parts bin there's an extra two next to it, these can be used to store the alligator clips and any other kind of probs you may choose to make, this helps keep everything looking nice and neat.
As always if you have any questions id be happy to answer them and thank you for viewing!