There shouldn't be any data flow when all you're doing is charging.
If Apple simply followed the spec and reserved the data pins for transferring data then there would be no problem and the iPhone would draw 500mA like any other USB device that does follow the spec.
Yes, the phone would charge slower but it's this non-standard 5W/10W switching that others try to mimic that is most likely causing the problem.
Apple compounds the problem by repeatedly adjusting these voltage and resistance levels which is why some chargers start or stop working when new iOS versions are released.
They needlessly created a system that demands more precision than the USB spec allows for.
Data flow is irrelevant. You said that there should not be any voltage on the data pins, when this is clearly a violation of basic physics. When you plug in a USB cable to a USB port the spec determines what is connected - by using the data pins.
As far as 500 mA goes, that was broken a very long time ago, and long before Apple. While the official spec calls for 5V DC at 500 mA max, the majority of PC ports and hubs have been providing up to (and sometimes beyond) 1 amp per port.
Providing 5W per port is already a violation of the standard (P= IV). Identification of connected devices without using a host controller also is, but then that's what every USB phone charger does.
Apple's chargers are based on a reference design from iWatt, which designs electronics for a range of companies, and they have been demonstrated to work safely and effectively to deliver charging current that both the charger itself and the device it is charging have identified is safe.
Where it breaks down is that the cheap knockoff chargers are compromised by building them to a price - and this price means that they lack many of the basic safety features that go into a device that converts mains voltage into usable low-voltage DC. You end up with frequently unsafe chargers that can potentially harm the user, and also deliver noisy unfiltered voltage that can damage charge circuitry inside your phone.
The blame is not on Apple here. The blame is buying a $2 charger and thinking "oh, it's the same, but cheaper". It really isn't.
The trace separation between the high and low sides of the circuit alone make me shake my head in disbelief with some of those knockoff chargers. I am amazed there haven't been more fires or electrocutions. Maybe they just don't get reported.
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Complete and utter BS. Apple blaming a crappy "chip" that fails miserably on "off brand chargers?".'
More like they are trying HARD to stop people from buying outside of Apple. And willing to break your device own purpose. They probably coded it to overheat if you use an off bread device.
// detect charge
if apple brand, continue charging.
if not, overheat and blow it up.
then LOL and blame them Chinese
// end code.
Shush kid, the adults are talking.
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interesting theory..
Apples deliberately breaks your i.Device if a third party changer is used ? If only they did this on purpose to get it in the press, and they'll be all over it like wildfire.
Then again, use a wrong voltage, or other charger with any other phone interchangeable (if you even could), it just won't work, not break it.)
I see your point though. This was never done in the past, so why do it now?
That person who who a "non-Apple approved" charger, and the article claimed their iPhone exploded... This is a case of pure hype. since all that would have happened is the charger wouldn't have worked..
But THIS ? Maybe its a move by Apple, to clamp down on
not to use third party chargers.
Seems to be a shame, because people want the convenience of two usb ports on a single charger, or other good device(s).
Apple again, controlling the market
The chip is expecting smoothed, filtered, voltage-regulated 5V DC. This is trivial to produce, if your charger is designed and built properly. Making a regulated 5V output is trivial, and you don;t even have to do it yourself - there are ICs available that do all the work for you - you just need to lay out the PCB at that point.
What happens in the case of crappy chargers is that these corners are cut and you end up with noisy DC on the output, with voltage transients, ripple, drift, etc, that the charging chip has *some* ability to clean up, but it has limits. If it's pushed outside of its operating range then there is the possibility of damage - especially if you keep feeding it voltage spikes above 5V.
Go and put a scope on the output of an official Apple charger (or one made by Belkin, or Amazon, or Samsung, or HTC) and compare it to a knockoff charger and you'll see the problem in seconds.
That doesn't even address the problem that the knockoff chargers are frequently actually dangerous to use (to your life, not just to your phone) due to dangerous practices involved in the board design that cut safety corners to get the price down.
