Step 2: The Charging Circuit

Picture of The Charging Circuit

For this project I've stolen a charging circuit from an Emergency iPod charger I got off ebay. You can find these all over the place. The key is to find one that will work with an iPhone.

Apple decided to have it's newer iDevices not follow USB standards. When an iDevice is plugged in, it checks the data tabs on the USB to see what it's plugged into. Depending on what it finds, it sucks more or less power, which makes sense but is annoying because NOTHING ELSE DOES THIS. Thus no charger out there has any power flowing to the data tabs.

So the key is to find one that works for your newer iPod or iPhone. If you have an older iPod or iPhone when you don't really need to worry all that much.

(For a USB Version of this, check out this instructable.)

If you want to make your own circuit you can always use a Mintyboost kit.

btran74 years ago
does anyone know for which what generation iPhones/iPods won't be able to use a normal USB charger?
JoshuaZimmerman (author)  btran74 years ago
iPhone 3GS and 4. The most recent iPod Touches.

(Though some of my customers have reported that the USB charger work with their iPhone 4s. I guess China changed the circuit without tell me. Damn Chinese!)
Thanks. I was wanting to make one for my 2nd gen iPod touch so i'll make the regular USB charger.
jmarye4 years ago
Do you see any problem as to why this would not work for the EVO 4G, with the necessary charging cable of course.
JoshuaZimmerman (author)  jmarye4 years ago
Not really. It "should" work, unless the EVO needs some special USB requirements. My parents have cheap Verizon phones and for some reason they won't charge. They give a weird error about how "This charger is not authorized."

But this isn't the kit for you. You want a USB charger.


This one uses a cable with an iPhone/iPod plug a the end.
where did you get your charging circuit? is it all in one and you just took apart the other end of the charger? I'm a bit confused.
i think this is what he used:

keseth4 years ago
What kind of usb charger has this? All that I've seen connects through a usb head :)