World's Smallest DIY Pocket Power Supply

Power Supply is a fundamental device in any electronics lab . The major downside to them is that they are often bulky and are not very portable. if you want just a variable voltage output with step down voltage these big supplies don't make sense.So, Here I present you World's Smallest DIY Pocket Power Supply.This Supply is so small that it fits any one's pocket and is capable of many functions.

Also Check My blog for more :- http://hardiqv.blogspot.com/

This Pocket Power Supply has Following Features:-

• LED Display For Displaying voltage output .
• Output Voltage range from 2.5 v to 30 v.
• Input Voltage range from 5 v to 35 v.
• Output Current has high as 2.2 to 2.5 amp.
• No need of Heat sink.
• Very small fits in any pocket.
• Has variable output voltage.
• Voltage can be adjusted through a potentiometer.
• Terminal blocks for easy connection.
• feedback controlled ic

know more about IC here :- http://shink.in/fCQRX

Following parts are Required:-

• LM317T X 1
• 10uf/63v capacitor X 2
• 1N4007 diode or m7 diode(smd) X 1
• Terminal block X 2
• Led voltmeter X 1
• M3 bolts X 2
• small piece of perfboard or veroboard.
• potentiometer 5k ohm X 1
• BD139 transistor X 2
• Some wire
• 3d Printer
• Soldering Iron
• Lots of patience !!!

I have attached the schematic of the power supply . download and print it if possible to avoid any mistakes.

I have also attached the step by step building photos . So make sure you follow them so that it becomes easy for use.

soldering the transistor is tricky as we are backpacking each other .

Tip :- placing the transistors in some sort of vice will help to solder very easily.

The voltmeter that i purchased was having the wires soldered very badly.
So, I removed them and then soldered it with a clean solder joint.

Make sure that the transistor and LM317T ic are flush with PCB.

After you have succesfully build your PCB as per the schematic then You may need to remove the PCB from the Veroboard.

For this I used DREMEL but you can use any rotary tool or you can the PCB to size before hand.

To avoid copper particles going inside the circuit I covered the entire circuit with Cello Tape. So that short Circuit is prevented.

After the cutting the PCB to use a blower or good blow from your mouth to blow off any copper bits .

Remove the cello tape and then inspect the circuit visually.

The Power supply will ready to be used now and will work flawlessly.

But I Designed and 3d printed the case to provide it more strength and rigidity.

So stick Around.

To provide a strength and good looks a 3D printed case is a must.

I designed my case in Fusion 360. and It is a two part Design

For 3D printing I used simplify3D to slice the model and then used my Anet A8 3D printer to print It.

You will need to M3 Bolts to join the two parts together.

Here is the video Showing It in action.

So there You have it World's Smallest DIY Power Supply

I hope You liked This Instructable . If So, please considering Voting For me in the contest.