3 Parts, 2$ Twin Port USB Charger!




About: Crazy and creative Industrial design student at Kielce Technology University.

Nowadays this circuit is inefficient and will not charge smartphones. It is better to use step-up regulators in order to achieve good efficiency and charging current.

To make this you will have:
LM7805 (voltage regulator) cost: 70 cents
dual USB port cost: about one dollar
9V battery connector cost: nothing! (i have got this from 9V battery)
and hmmm... thats it!
you must have soldering iron and solder of course.

Solder everything tohether using tips from picture 2.

And thats all!
You've got it!
Dual port USB charger!

Thanks for vieving!

(don't forget to rate!)

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    9 Discussions


    8 years ago on Introduction

    be more specific with a simple schematic. Many reades are very beginners and amateurs. A well project idea is well supported to the end. So also we need a proof that works...plug an mp3 showing that is charging etc....

    For this is not enough to charge an Ipod or any mp3. This is good to switch on a lamp, or led, or fan. Nothing more and serious than this....

    4 replies

    because a usb port is more than a red and black wire with 5 volts running through it. For any advanced usb charging device, it requires the other 2 pins as well. when you strip a usb wire, you notice a green and white wire as well. These are the data transfer wires that almost all devices require now to charge. it takes about 3.3 volts running across these 2 wires as well to "fool" a device into thinking it is connected to a computer or a "legit" charger. This charger seen here is a neat cheap idea for something simple like a fan mentioned earlier, but that's all its physically capable of running, as well as its low efficiency of giving off WAY to much heat not to be using a heat sink on that 5V regulator.


    Reply 8 years ago on Introduction

    exactly thanks brassjammer.....this is only good to operate a lamp or fan no gharging tool......noway


    6 years ago on Introduction

    You are at least 2 components short of an iPod/iPhone/iPad charger.
    With them, this would make an OK "emergency" power supply (as in, "my battery is almost dead, and I have to make a call desperately, and the power is out").
    But left with nothing connected to the USB ports, this will kill the battery pretty fast.
    The 7805 is normally used where you have a constant power source such as a 5-12V plugged in power adapter.
    It is however a good example of how to get 5V from a higher voltage source, although you didn't provide any sort of connection information as to what connects where - not even a schematic, which will leave the people that know less than you wondering how this works - and worst of all, not able to make their own.
    The idea is solid, and I encourage you to continue on, but you need to research things a bit more, and you need to share what you have learned better.
    Keep up the good work, and keep learning, and don't be afraid to ask questions.
    The only stupid question is the one you didn't bother asking!


    6 years ago

    Yes, could you please show us how you solder it?

    but how have you soldered the components? I love the idea of such a compact PP3 battery charger, but without a circuit diagram, it is difficult to tell just how it works.

    Kante Tech

    8 years ago on Introduction

    Wouldnt this cause the charger to heat up really fast if it is charge to devices that require about 5 volts from a 9 volt battery.