Przypuszczam, ze wtyk MicroUSB moze byc tu problemem.

"The micro USB pins are very small, and the power-carrying connectors, pins
1 and 5, are rated to carry 1.8 amps at 5 volts DC. That means that the
maximum charging power that can safely flow across the connector is 9
watts. But the iPad wants 10 watts to charge. It will charge on as little
as 5 watts, the output of most USB 3 ports and the specially modified USB 2
ports on newer Apple products, but needs 10 watts for fastest charging."

https://techpinions.com/why-apple-couldnt-go-to-micr
o-usb-charging/10212

USB Power Supply/charger Test
www.lygte-info.dk/info/indexUSB%20UK.html
www.lygte-info.dk/info/usbPowerSupplyTest%20UK.html
www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-a
pple-is.html

Ciekawie wyglada duzy port USB w IR przy 2.5A.
http://lygte-info.dk/pic/USB%20PS/15%2030W%20USB%20D
esktop%20Charger/Temp1719.png
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