Introduction: Easy USB Charger
This is an easy USB charger because you can get the electronic booster board already assembled. Just add the batteries, a couple of capacitors, the usb connector and nothing else.
Step 1: Materials
The main component is the PTN04050, it takes the 2.4 volts from the batteries and raise it to 5 volts for the USB. You can get it from the Texas Instruments site here.
You will also need:
2 100uf capacitor
1 USB female connector
1 battery holder
Wires
Step 2: Assembly
The assembly is pretty easy, just follow the scheme. Try to not overheat the terminal of the PTN04050 and be careful with the polarity of the USB connector.
Step 3: Finish
Find a nice case for your charger, an Altoids tin would be great, but I can't find one of that in my country so I will keep look for a case.
For testing the device at first I used my USB tester and then I tried it with my mp3 player, but there shouldn't be any problem if I were careful with the assembly.

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30 Comments
7 years ago
does anybody know if this will damage an iphone 4s at all
11 years ago on Introduction
it no work with psp
11 years ago on Step 3
an IPad will be more "picky"
11 years ago on Introduction
Just as an FYI - You can order samples of this item if you have a company (or if you enter a company name in TI's registration fields). The samples are free. I DO NOT recommend abusing this. I simply think those who own electronics companies should know.
11 years ago on Introduction
I tried this and it did not work it couldnt even charge my motorola phone. the w765 or somehing.
11 years ago on Introduction
No Altoids tins in your country that is TERRIBLE!!!!!!!! that's like not having duck tape.
11 years ago on Introduction
I'm not very good with schematics. Is my terribly drawn in mspaint translation correct? and could someone fill me in on the ? I've placed in there? thanks!
Reply 11 years ago on Introduction
sorry, bad labeling...
11 years ago on Introduction
im a storm chaser and need to charge usb instermentsin my truck you should do one like this one but step it down from 12v car to 5v i would love to see that one
Reply 11 years ago on Introduction
Just FYI if you're really in need of something like that there are tons of devices out there like this https://www.dealextreme.com/p/universal-usb-ac-car-charger-adapter-27057
However if you want to build your own you can check out this instructable https://www.instructables.com/id/12v-to-USB-adapter-12v-to-5v-transformer-great-/
11 years ago on Introduction
Why is the output capacitor placed on the USB connector instead of at the module? Quoting from TI's datasheet: "The stability of the module and voltage tolerances are compromised if the capacitor is not placed near the output pin."
Granted, it's good practice to place an electrolytic close to the load, that's primarily to improve transient response (also as noted in the datasheet) though for charging applications, load transients may be minimal (but YMMV, as always).
11 years ago on Introduction
How would you make one with 4 or 5 batteries to get up around the 5 volts needed? Would the electronics be any simpler or cheaper?
Reply 11 years ago on Introduction
Get yourself a cheap car charger for your phone, the inside board will already be capable of dropping ur Vs to the desired mount. This should work as long as ur batteries aren't too low or too high in volts. (and beware, think and ask yourself if potentially damaging 400$ worth of electronics is worth getting a few more hours of charge)
Reply 11 years ago on Introduction
You can't get exactly 5 volts from 1.5v batteries, so Im pretty sure you'd need the regulator no matter what.
11 years ago on Introduction
how well would this charge a 6th gen ipod nano? its an 8 gig model if that makes any difference.
Reply 11 years ago on Introduction
You will need 1 150k resistor and 1 100k resistor. Tie on end of the 150k to the +5, and on end to the 100k. Then take the open end of the 100k and connect it to ground. Then attach a lead to the connection between the 2 resistors and connect it to the 2 data pins on the usb. That should let it work. The device should draw about 600mA total from the batteries.
I recently built an iPhone solar charger. I had the same problem.
Reply 11 years ago on Introduction
could you show this in a real life pic and not a dig. i would like to see how that looks
Reply 11 years ago on Introduction
I would really love to show you a pic, but I am currently upgrading the system to make it charge better. I will upload a picture of the upgrade when i'm done, but right now it's all torn apart.
Reply 11 years ago on Introduction
oh bang on! thanks
11 years ago on Introduction
UPDATE: the module that this poster mentioned is available via the ti website as a free sample. you can click the link the poster provides which will directly place you at the right module. click sample or buy and register a myti account. note you MUST provide a business name(i use my last name combined with the hobby im into which is legal by law and you do not need a verified business with the government either) you must also provide a url so just sign up for a free website at www.weeble.com or similar and activate the account. you do not need to create a webpage. than continue with the sample checkout. it will ask for end user info. click same as button unless youd like it sent elsewhere, check out and youll get the fedex confirmation email next day or same day if its between 9-5.
im getting mine tomorrow:) and along with that when alls said and done ti gives you other tsamples you may be interested in in the same emails. click them to get more free samples. you must choose standard ship in order to be totally free of cost.
ti only allows 5 samples per request but multiple requests may be possible. choose any type of business you want i put electronics amusement as mine.
hope this info helps those trying to build these.
sweet instructable i will post my results when my module arrives:)