Introduction: Worlds Smallest Power Supply !

Have you ever wanted tiny sized power supply that still pack lots of power, here's world's smallest power supply you can make under 6$ !!! Following Features will impress you that's for sure so why not make one ?

# Features

1. 3-25v Adjustable Voltage Output

2. Built in 720mAh Battery Backup

3. 2 Amp Max Current

4. Built in Live LED Voltmeter

5. Built in Voltmeter For Quick Measurement

6. In Built 3.7v Battery Charger

Step 1: Applications

1. Power Supply (OTG) on the go !

2. Measure voltage with it.

3. Do the Job of Many Power supplies 3v, 5v,9v,12v,19v,24v...

4. Charge 3.7v Batteries on the go.

Step 2: You Will Need

★☆★ Buy Parts from your online local store ★☆★

1. 3.7v Li-po Battery

2. TP4056 Lithium Battery Charger

3. Micro Usb 2A 25v Step Up Converter

4. LED Voltmeter

Step 3: Watch Full Tutorial

Watch Full Tutorial Here

Step 4: Making PCB's Compact

LED Voltmeter and Dc-Dc Converter has few leads which may puncture the battery and take up lot of extra space, so use dremel tool or sand paper to make these pcb's flat at the bottom so that battery can be effectively installed here

Or Yo can use flathead pcb wire cutter to do this job , just don't apply too much force otherwise pcb tracks will be damaged.

Step 5: Make the Connections

Make The connections As Showed In This Block Diagram.

1. Connect the tp4056 board to the battery

2. Connect the negative terminal of the battery to the dc-dc converter

3. Connect switch between positive terminal of the battery and dc-dc converter

4. Connect LED Voltmeter at the output of dc-dc converter

Step 6: Stick Togather !

Well Done Your Connections are finished !

Now Stick all the parts togather in a compact form factor as i've done in this picture.

If you like this instructibles ,then check out my Youtube Channel .

Step 7: Some Extra Safety Tips

1. As you are dealing with li-po battery's , make sure not to puncture,smash,tear or casue any kind of damage to the battery it may cause fire hazard. Do it at your own risks.

2. Don't try to measure voltage grater than 24v with this power supply's voltmeter It can damage the dc-dc converter.

3. If you connect any inductive load ,there is chance of causing damage to dc-dc converter , so connect diode at the output. diode will drop 0.7v but save your power supply.


GauravJ14 made it!(author)2016-11-02

Hi. Thanks for a brilliant instructable.. This can be used to charge bose speaker. It's battery needs 20 volt output.

TianxiZ1 made it!(author)2016-09-24

If you use a 3 wire voltmeter, the output can go below 3V

bptjr made it!(author)2016-09-23

bptjr The tp4056 charge board comes stock to current limit at 1 amp . Is this too high current to charge the battery you describe ? Or did you change the current limit resistor on the board ? Great project I plan to build one Thanks

MirzhaK made it!(author)2016-05-29

can I use this power supply to charge my laptop?

Input : 100-240V ~ 1.8A

Output :19V - 3.42A

ovi20k made it!(author)2016-05-23

are those components available in

wstewl made it!(author)2016-02-28

Made it. Fun, cute and somewhat useful. I was not expecting the ugly waveform when I looked at the output on an oscilloscope. Set to 12.0V, and looked at the 'ripple' on the output line with no load. See photo below. There is an average noise of about 1.3V p-p distorted saw-tooth waves riding on the 12V level with irregular jumping levels. I presume an applied load would lower that amplitude some. I strongly recommend a heavy filter capacitor to smooth out some of that noise/ripple.

Power Supply noise.jpg
tonep made it!(author)2016-01-24

Nicely done! I made almost exactly the same here, but it has a few extra features and the lithium cell is much bigger (taken from a defective portable charger) so the size is much bigger, but the main components are the same. For those interested in knowing if a bigger size cell works on the same charger,the answer is "yes". I have been charging and using it for about 4 or 5 months now.

brianfit1 made it!(author)2016-01-21

Love it. As an alternative to flat-sanding the board, you could press it into a slab of Sugru, and shape it around the Li-po for a nice finished look.

wstewl made it!(author)2016-01-19

1) does the battery get automatically disconnected from the circuit when the 'high power' USB input is used?

2) using just the battery, what output current is available from the circuit (at 5V, or at 12V)?

Kedar+Nimbalkar made it!(author)2016-01-20

in high power mode battery is disconnected since we're keeping battery switch off, and @5v 1.2amp @12v 500 ma.

wstewl made it!(author)2016-01-20

Thank you for answering my questions. Nice project.
When I build it I'll have to be careful about keeping the switch off when using external power.

jr2233 made it!(author)2015-12-26

Is that small battery to be used for the charging circuit or is it for whatever I am turning on? Can I replace that small battery with a large 5,000 mAh battery? Will the 2 amp charger be enough to charge it> Hope someone answers me.JR

Kedar+Nimbalkar made it!(author)2016-01-20

There's no problem keeping Tp4056 as chaging circuit with bigger battery,but if battery is higher capacity then use high power handling dc converter.

lmcwill made it!(author)2016-01-19

No. This will handle single cell lipo batteries. Charging a large lipo (multi-cell) battery requires a balancing charger to keep the charge rate under control.

ac-dc made it!(author)2016-01-19

He wrote nothing about using more than one cell, so "no" is premature and incorrect. There are ~ 5000mAh Li-Ion cells and you could use as large a cell as you want providing there is no minimum charge rate specified by the manufacturer.

Yes a 2A charger would, in most cases, be enough to charge a 5Ah battery, but the charger is not 2A, it is 1A max, but the input is USB so your source could be even lower at 500mA.

Even as low as 500mA could work but it would seem undesirable to have to wait that long so I would recommend that you find an alternate power source and charger capable of more than 1A, which will raise the build cost a little but so does the 5Ah battery.

shaheed made it!(author)2016-01-01

how to adjust voltage.....?

Kedar+Nimbalkar made it!(author)2016-01-20

with the potentiometer on dc-dc converter

evdj made it!(author)2016-01-04

Is it possible to use this power supply as a battery backup with continue connection to USB power?

Kedar+Nimbalkar made it!(author)2016-01-20

Yes its possible to continue use with usb input.

ac-dc made it!(author)2016-01-19

Yes but that would be foolish, to bother with a charging circuit and battery at all when you could eliminate both and just use a 5V step up power supply. There is a narrow range within which you could have more current for a short period from the battery but since the USB input is the limiting factor and that in a power outage you are presumably using some OTHER battery to power the USB, it would make lot more sense to just use a different boost or buck power supply to convert the larger input battery to the output voltage and current level needed.

StuartB44 made it!(author)2016-01-19


The little square blue component with the tiny screw head is a potentiometer (variable resistor). Looks like that is how you adjust the voltage.

Kedar+Nimbalkar made it!(author)2016-01-20

Actually it is a dc-dc step up converter .

michael_nonan made it!(author)2016-01-19

do you need to adjust the voltage everytime you turn it off and on again? Or do you get same voltage from before?

Kedar+Nimbalkar made it!(author)2016-01-20

You get the same voltage seted before.

ErixM made it!(author)2016-01-20


very useful and clever power supply.

I've just one question, do you think it's possible to use the output power of the DC/DC during battery charging ? or it's not recommended ?

Thanks in advance for your help.



Kedar+Nimbalkar made it!(author)2016-01-20

Hi , Erix
Yes power supply can be used during charging with no problems.

WannaDuino made it!(author)2016-01-19

Nice project, i go to make also one.

Jobar007 made it!(author)2015-12-23

At 3v vs 25v, qhat is the amp dra?

Kedar+Nimbalkar made it!(author)2015-12-23

25v @ 500ma
3v @ 2 Amp

Jobar007 made it!(author)2015-12-28


pwllheli made it!(author)2015-12-25

Compact. Great ideas. Thanks

sanjeev.saxena.9231 made it!(author)2015-12-24

Very nice.... ?

elfakes made it!(author)2015-12-24

Great instructable! So the voltmeter can measure other voltages but the source itself?

botronics made it!(author)2015-12-24

With new shipping restrictions imposed on Lithium Cells, is it difficult to get Lipos shipped to the USA from China?

WOLFMANNACTUAL made it!(author)2015-12-24

If you go through HobbyKing you can get Lithium batteries from their stateside outlets. I buy my lipo batteries from them all the time. Can not beat their prices

rrhill made it!(author)2015-12-24

Work for Raspberry Pi? Can it be configured to power the Pi in a power outage on just the builtin battery with minimal power loss (Pi continues running in a power failure) and signal the Pi to shutdown before the onboard battery fails?

Yonatan24 made it!(author)2015-12-24

Good idea, But 2A wouldn't be enough for 99% of my projects :)

makeosaurus made it!(author)2015-12-22

This is really cool! Do you connect it to the circuit third through spare wires or the USB??

Kedar+Nimbalkar made it!(author)2015-12-22

i used wires to connect them.

About This Instructable




Bio: Ideas Into Reality !
More by Kedar Nimbalkar:DIY Wireless Charging for Your Gaming Mouse ! - Goodbye Batteries Make Coca Cola Soda Fountain Dispenser Machine at Your Home Fridge !How To Make EMP Gun !
Add instructable to: