with this circuit you can charge an apple product iphone,ipod etc with any charger.it's simulates the 1 A apples charger. this circuit it makes the iphone think that it is connected to the original apples charger because it reads the voltages from data +/- of usb
The source it suppose to be the charger which can't charger your iphone exp a sony charger and the voltmeters are for red wire of usb (5 volts) the white cable for data - (2,7 volts) the green cable for data + (2 volts ) and the black as ground. If you want to build it in real life all you need: a usb female, a usb male and 2 potentiometers of 10 k connect as the circuit and give the voltages as I gave them. after that connect the male of your circuit to the sony charger for example and your iphones usb cable to the female usb of your circuit