MacBook Pro 2017 Charges iPhone Slow w/ Adapter

[Sovon Halder]

I got a 2017 MacBook Pro 13" at home. And a 2011 iMac at office.

And I got 2 usb-c dongles Juiced Systems Bizhub and Apple Digital AV adapter.

When I connect my iPhone to the computers, I get the following current readings..

1. Bizhub + Lightning cable + MBP

• Current Available (mA): 500
• Current Required (mA): 500
• Extra Operating Current (mA): 0
• Sleep current (mA): 500

2. Digital AV Adapter + Lightning cable + MBP

• Current Available (mA): 500
• Current Required (mA): 500
• Extra Operating Current (mA): 600
• Sleep current (mA): 1100

3. Lightning cable + iMac

• Current Available (mA): 500
• Current Required (mA): 500
• Extra Operating Current (mA): 1600
• Sleep current (mA): 2100

I was pretty satisfied with the purchase of Digital AV adapter since it does some useful things that the Bizhub couldn't do viz. updating iPhone OS using cable+computer, not dropping plugged in devices when pass through power is removed, charges macbook at 55W (bizhub @49W) etc. But this is weird.

How come a 8 year old obsolete machine with USB 2.0 standard provide 2100mA current while a relatively new computer with Thunderbolt 3 standard provide only 1100mA. I get that it probably is an adapter issue, but I would have guessed that an apple made peripheral would not be a limitation specially when the USB-A port seems to be 3.0 standard; I checked file transfer speed. Anyone have any idea ?

 

[maflynn]

I get that it probably is an adapter issue

You answered your own question, its probably not the laptop but the adapter. You cannot say the new laptop is inferior at this point because you cannot use it like your old computer, i.e., charge your phone w/o the TB adapter.

 

[Sovon Halder]

You answered your own question, its probably not the laptop but the adapter. You cannot say the new laptop is inferior at this point because you cannot use it like your old computer, i.e., charge your phone w/o the TB adapter.

I'm not saying new laptop is inferior. It's just little unexpected that Apple nerfed their own adapter like this. Third party adapters I can understand but I thought a 70$ apple adapter would be flawless. I bought an adapter because I thought lightning port would go away soon, so investing in an adapter rather than a cable would be a better idea.

Anyways do you know any other good adapter that does just as good as connecting the devices directly to the computer itself?