User Guides DIY Universal (ipod/zune etc) usb charger

Folks,

Here's a very simple method to hack up your own universal usb charger. Takes hardly half an hour. It can be used to charge any device that can charge through USB.

I have an ipod and a zune lying around, but both didnt come with chargers. I have to always connect them to the PC to charge them, which is a pain. Now my bro is going on a trip for a week and since he wont have access to a PC, he wants a charger for the zune. I decided to build one.

Parts needed
1) A 5volt regulated DC power supply
2) A female USB connector. If you have a USB extender cable, you can cut it to use the female connector
3) Some insulating tape, wires (and some ingenuity).

USB standard is very simple. See the table and pin layout below.
You just need to provide a regulated 5 volt DC supply to the correct pins. That's all that's required to charge a USB device.



I have a power supply for my external HDD which I decided to use for this project. It's output is the standard male molex connector (same as used in PC SMPS) with +5V +12V and GND.
Pin layout is as below. Red wire is +5V and the black wire just next to it is the GND.



We just need the +5V and ground. I used a female molex connector and cut the wires to separate out the +5V and GND.
Now we just need to connect this to the +5v and GND of the USB connector. Rest I guess is self explanatory - connect the wires, and you are done :)

Instead of a female USB connector, I cut a USB extender cable and used it.

Now for the pics.

The power supply and the AC cord


Molex connector - red and black wires connected to the red and black wires of the USB cable.


The whole setup - showing my zune charging :)


If you dont have a 5v power supply, you can use a standard Nokia charger as well. It's output is +5.7v. Just add a diode in series to drop 0.7 V - now you have exactly +5V :)
Pls note - I havent tested using Nokia charger, but I'm sure it will work. Just make sure you use the diode, else voltage will be too much.

I hope this will be useful to people who dont have ipod/zune chargers. Do let me know your comments.
 
full points for the diy, but cheap chinese usb-mains adapters are available for ~100 rs

Mr Barber, you could have tried bimapally :p
 
greenhorn said:
full points for the diy, but cheap chinese usb-mains adapters are available for ~100 rs
Mr Barber, you could have tried bimapally :p

Yeah...I think it's available at thakaraparambu road also...but then I don't get to DIY (D-I-Myself) :D
Actually situation was like this...my bro was leaving on a trip at 6AM today morning...and he was moaning about not having a charger at 11PM yesterday night...so I had to quickly cook up something like this.
 
Thanks for all the encouragement guys!! You made my day :)

Next step - after hunting through my old junk, I found a small unused 5V power adapter that was used for my old external TV tuner box (which is not working now anyway). It is very small - like a mobile charger.

So it's gonna be 'bye bye' to the bulky power adapter and AC cord. Now it'll be just like a mobile charger with a female USB adapter at the end of the wire instead of the charger pin.
 
greenhorn said:
full points for the diy, but cheap chinese usb-mains adapters are available for ~100 rs

I have tried one(40/-:ashamed:) of those but dint work for my Zune 30 :( was this a one-off case? Do they usually work? I dont mind buying a philips(600/-) one if they do.
 
^^ If u give 5V and GND to the proper pins, it will surely work. Charger needs to be able to provide sufficient current also.

If you have a multimeter, just open it up and check the voltage while charging the zune. I think it might not be supplying enough voltage.

On the net I found some circuits for charging ipods through USB using 2 dry cells. That way you get only 3V charging potential. Might work with some devices, might not work with others.
 
PaulBarber said:
^^ If u give 5V and GND to the proper pins, it will surely work. Charger needs to be able to provide sufficient current also.

biggest issues with these cheap chinese thingies. one cheap example i saw was rated at 3~9V, 100mA

USB is 5V, and i think with only +/- 10% tolerance
 
^^ it might work, but why take the risk? According to USB documentation, "The specification provides for no more than 5.25 V and no less than 4.75 V (5 V±5%) between the positive and negative bus power lines."

You can get a diode from any local electronics shop. Get a commonly used one like IN414 (IIRC).
 
would the diode have to be soldered or can i just connect & secure the whole thing with insulation tape?

PS.. i've noticed the sony ericsson chargers are 4.9 volts but theres just one in my house and it is in use.
 
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