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Hoemade bike USB Charger not charging iPhone Answered

I made a bike phone charger using a motor as a generator connected to a linear voltage regulator. The output current is stable at 5.05V and 1.1a (measured with a multimeter). Any USB device works, except iPhone and other Apple devices. It starts charging and 2 seconds later I get “This accessory may be not supported”

Anyone knows what’s happening? Thanks.


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2 years ago

Apple does not conform to the USB charging standards.
Firstly Apple devices need a really stable (ripple free) power supply.
Secondly you also need to provide the correct voltages on the data lines so Apple products "recognise" the chargers capabilitites.
Where a normal Android still charges at 500mA without the voltages on the data lines, Applejust states you are not using an Apple charger.
There are Wikipedia articles explaining what voltages on the data lines correspond to what charging mode, from 500mA to normal over to quick and full power charge.