Introduction: DIY More Efficient Long-lasting USB or ANY Charger
In this tutorial I will guide you into making one of the most efficient long-lasting USB charger out there. At the moment there are two types of chargers out there.
The first charger takes a higher voltage and cuts the voltage down producing heat, in other words wastes energy, and as the batteries or source are put in use, the battery power beings to decrease to the point where the batteries can not power up five volts which causes you to switch batteries. But the batteries still have power in, just not enough to power your device so DON'T THROW YOUR BATTERIES AWAY.
The second charger I believe is a more efficient design such as a MINTYBOOST . It takes a lower voltage and it bumps it up to the voltage needed thus not wasting as much power. The only drawback is that you are now stuck with a shorter lifespan, which for some isn't bad, but I like the life span and the efficiency.
Here I will make a 4 AA battery charger using the "AnyVolt Micro" from Dimension Engineering. It will bump the voltage down while batteries are fully charged and then when the batteries reach a much lower voltage say half power it will switch automatically to bump the power up to a desired voltage. Thus using your batteries thoroughly.
While writing this I have run across another marvel from Dimension Engineering called the LVBoost. This device will run the batteries lower thus making your device run longer. BUT the device only goes to a max 5volts at 1 Amp so this will only work for devices that can operate at 5 volts, which would actually work for this project with a smaller battery pack. I wanted to make something that I could use 4 AAs or higher and be able to power something up to 14 volts.
There is also some minimal SOLDERING for newbie's!!!!
Step 1: Materials
Materials
1 - USB Female Connector preferably one already wired and neat so you can put it in your favorite project case. (I used one that came with my motherboard) - $Free or cheap $3 USB extender
1 - AnyVolt Micro - $20-25 (the most expensive part but you'll make it up with those expensive AA's ur gonna be getting through time.)
1 - 4 AA Pack with batteries (built in On/ Off not required, but I figured I make sure that im saving power) - $4-5
1 - 10k Resistor - $pennies
Soldering Iron - $(should have one otherwise this may be the most expensive part)
Any Shrink Tubing if you choice - $again pennies
Step 2: Take It OFF!!! and Put It Back On....
Strip the wiring on your USB connector, you should see 4 wires RED, BLACK, GREEN, and WHITE.
Strip the wiring on your battery pack revealing the Black and a RED wire.
Solder the Red from you battery pack to the Vin port on the AnyVolt.
Then the Black to the GND port. You may want to put the Black wire form the USB connector here as well.
Now finally the RED wire from the USB should go to the Vout port on the AnyVolt wire to the Voltage Out on you AnyVolt.
Step 3: TEST
Test it out with a Meter and make sure you tune the POTENTIOMETER on the AnyVolt to the right voltage (USB uses 4.8 to 5.2 volts so i put it at a sweet 5v flat.). You can now use it on a USB device, it should power up. i tested it on my "Teensy"http://www.pjrc.com/teensy/ and it powered right up. But my iphone wont work...... next step.
Step 4: IPhone Support
Iphone's and Itouch's and other devices need a signal from the White and the Green wire in the USB cable. This tells the device that it needs to come off battery power and go to a usb power.
I'm not an expert but I'm a little stupid, I just touched the green and white cables and it actually worked. The Itouch went into charging mode.
Now i just wanted to be safe so i bumped the 1.2 volts down with the 10k resistor and it worked just fine.
Step 5: Ain't It Puuurrrty....
I haven't dressed mine up yet, but you can now package it anyway you want. You now have an Efficient USB power device!
Step 6: All This for Just This?!?
Finally, by turning the POT on the side, the AnyVolt can power up to 14v and power down to 2.6v.
This means you can power any device just by tuning the Voltage to the device specifications. By the way, you might have to change the connector on the end by utilizing that black and red wire again.
I also put a picture of the device with nothing changed running off 2 Batteires showing it will go down to 3v and lower. The 2 red wires are there to complete the connection so it will work.
CONGRADULATIONS!!! you have now made a USB charger that is more efficient and longer lasting than most if not all commercial portable USB chargers!

Participated in the
Earthjustice United States of Efficiency Contest
28 Comments
13 years ago on Step 1
okay my cuz has a new i phone and shes going to europe and im making something like this but the total is 4.8 volts its just a battery holder diretly to the usb hub would that work effectively
Reply 13 years ago on Introduction
assuming that you are using rechargable batteries, and you want to keep this cheap, try putting 5 or 6 batteries in series and attaching a 5 volt regulator plus a resistor, effiency should be ok because you are taking 6 or 7.2 volts and stepping it down to 5
Reply 10 years ago on Introduction
yeah i guess im trying to be green since using a resistor would waste power.
Reply 10 years ago on Introduction
first of all... this was a long time ago... second of all, how is using a resistor not "green" i stated stepped down, that implies a switching regulator, but instead of using a boost regulator you could use a buck regulator, which is in general much less expensive. The resistor is just to drop the voltage on the signal pins.
Reply 10 years ago on Introduction
aswell as instead of using a potentiometer like the regulator you have.
Reply 10 years ago on Introduction
thats works but if the batteries drop to a certain voltage the iphone and some other smart phones will not charge with the low voltage even thought the batterys arent dead
11 years ago on Step 2
I got 3.55 V .. is it normaL??
Thank you!
CYa!
Reply 10 years ago on Introduction
in can be if the any volt isnt set to 5v. adjust the anyvolt and a use a multimeter to get it to the right setting
11 years ago on Introduction
Just wondering how hard it would be to build this so it used 4D batteries instead of 4AAs?
Reply 10 years ago on Introduction
sure dont see why not
10 years ago on Introduction
This is exactly the kind of project I was looking for! I was wondering if I could adapt it to use different batteries like a laptop battery pack? What do you think?
Reply 10 years ago on Introduction
sorry for late response. but yes you could as long as u can stay within the input voltage limits of the anyvolt. they do make a bigger version http://www.dimensionengineering.com/products/anyvolt3
that can take much higher voltages
13 years ago on Introduction
also were would u get the anyvolt like in a store i live in the U.S i searched it on radio shack but nada
Reply 13 years ago on Introduction
no i couldnt find anyone that had it except some online robotic stores. and if wired correctly i dont know why a hub wouldnt work just becareful of using ur hub in conjuction with other devices and connected to your computer.
13 years ago on Introduction
is there any alternative to he anyvolt micro?
Reply 13 years ago on Introduction
eh only the bigger anyvolt lol not sure its why i used it
13 years ago on Step 6
is this unit safe to use with recharable batteries, NiMH in particular? or will it destroy the batteries by deep-draining them like joule thieves do?
Reply 13 years ago on Step 6
not sure but like on mine i had a switch in the battery pack that stopped any draw from the batteries at all.
13 years ago on Introduction
so you can just connect the white and green to make it charge
Reply 13 years ago on Introduction
worked for me but i put a resistor just to make sure nothing big would go through