USB Wall Charger


[rbhays] did this sweet little hack back in 2006. He took a Motorola cellphone wall charger and modified it into a USB wall charger. He needed to charge his iPod, but misplaced the original charger. A replacement would have cost him $30. So he did what any respectable hacker would do, he cut up something else to make it work for him.

He had one sitting around that was equipped with a mini USB end. He checked it out and it was the perfect voltage. Some commenters below the project noted that their motorola charger had a higher voltage rating than his. Those would still work, but would require some extra steps to bring the voltage down.

After some careful soldering, and a bit of super glue, he’s left with a perfectly good wall charger. He can charge most things that only use the juice from the wall. Some things refuse to charge though, such as Zunes. There was another project by [Cvesey] that claims to charge Zunes as well. While wall chargers may be available fairly cheaply now, many of us have some of these cellphone chargers just sitting around. Now we have a use for them.

20 thoughts on “USB Wall Charger

  1. That’s actually amazing because I have almost exactly the same phone charger, and the end that connects to the phone is broken. I posted on the instructables forums asking if this would make a suitable USB charger since it outputs at 5v but no one got back to me :( I guess this answers that.

    My question is, why didn’t he leave the cable? Having the USB female end embedded into the shell seems to make it less versatile. If I just cut off the end of my cable, mark the polarity right, and splice it with an existing USB cable, I should be set, right?

  2. Some devices (like the razr phones) require more than just 5 volts from usb. To charge, you need pins 2 and 4 in the connector connected to ground via a resistor. This puts the phone in “charge” mode.
    This may be the reason the Zune won’t charge with it.

  3. my wifes camera came with a usb wall charger, for you to plug it’s usb cable into, but I plugged my htc touch into it, and fried the touch. Camera still charges okay, so does ipod, but I wouldnt make one with higher than 5v.

  4. Not a new hack but certainly a very useful one, I’ve done the same with an old 5v 2A power supply meant for some old obscure magneto-optical drive. I didn’t take the PSU apart but instead wired up a dual USB port hacked out from an unused PC front panel (dead motherboards’ dual USB ports work equally well) and superglued it to the top with added hot glue for extra stability – it doesn’t look very slick but works very well for my mp3 player/Archos PMP/mobile phone/rechargable USB battery packs.

    It’s not just “wall warts” that this particular hack is good for, if you have a cigarette lighter adaptor for a mobile phone kicking about doing nothing then chances are it outputs 5v – look at the label & check with a multimeter :)

    One important note to be aware of is amps output, the USB spec is 500mA so chargers that output 500mA or higher won’t give you any problems. 1A & higher ones are great for dual USB sockets so you can charge two devices without worry.

  5. Jeze – just read the instructables comments – there are a load of uninformed people in there…

    To clear up a couple of things

    USB is rated at 100mA max draw until the computer says OK, then the device can negotiate upto 500mA

    This means that the battery charger will not kick in until the computer OK’s it.

    Enter the charging specification, this says that a dumb power supply can pull the pins to rails to allow the device to enter a charging mode without negotiation.

    The reason why new devices don’t charge with a dumb implementation is because they follow the (new) standard, the reason why old devices work is that before the standard it was apparent that many Laptops would happily pump out up to 2A without any negotiation.

    Nothing to do with corporate greed, in fact quite the opposite.

  6. That’s cool and all for 2 years ago, but usb wall chargers are all over the place now. I say bad HackADay. If you want a usb wal charger, let me know and I’ll send you one of the ten I have for free.

  7. @ mike sty

    I chose to embed the usb jack to make it more portable. (no cable to wrap). Also, most device have thier own usb to proprietary connector, so having a cable sticking of the charger isn’t very useful (IMHO)

  8. @#12: Agreed. I have no less than 2 car chargers and 4 wall-warts that provide a “charging” USB port. Meritline carries them for like 5 bucks shipped.

    The part that pisses me off is that I don’t think even the new “charging standard” is actually a *standard*, as it’s always a crapshoot whether a given mini-B device will charge with a given mini-B charger. I have (at least) an HTC phone, a Motorola phone, and a Creative MP3 player, that each need a separate wall wart — of the ~5 mini-B chargers I have, none will charge all 3 of them. One charges the HTC and the Creative, but no the Moto. One charges the HTC and the Moto, but not the Creative. One charges the Moto, but not the HTC or the Creative. It drives me crazy.

  9. With the current trend towards sustainable development, clean energy, it is not surprising that solar energy has become a source of energy the most popular alternative. Free and available everywhere from the sun’s energy can be used to power everything from tall buildings to your MP3 player. The energy of the sun are usually harvested by solar panels made of photovoltaic cells. These cells can convert solar energy
    into electricity that can be used for … Read entire article »

Leave a Reply to sPiTfIrE-K1LLCancel reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.