How does iphone charging work?

[jdmz]

Does the phone control when to stop charging or does the charger? So.. when the battery is full, and the charger is defective, charging will not shut off? I got a 2A car charger that I might not trust if it's controlled by the charger..

 

[takeshi74]

Controlled by the device. The device will pull what it needs. See also all prior threads on chargers as this is a very common topic. A defective charger is a charger that doesn't charge. Why would you attempt to use one?

 

[Ray-]

Definitely controlled by the phone. The charger can't "push" more charge to the phone than the phone is requesting. That is, unless something goes explosively wrong.