6 Replies Latest reply: Jul 15, 2012 6:40 AM by Tony O.
spald Level 1 Level 1 (5 points)
I know most USB 2 ports don't have the necessary current to charge it, but USB 3.0 is rated at 900 mA. Even though its not capable of syncing at the higher speed, will it be compatible with charging at a higher current?
  • Craig Brady Level 4 Level 4 (1,790 points)
    USB 3.0 is rated for 1.5 amps in low or normal data speed, and 900mA at highest speed. Dedicated charging ports go to 2.5 amps, but are useless for syncing, as they do not support data. USB 2.0 ports can certainly charge the iPad if rated high enough. Some will charge only when the iPad is asleep.
  • spald Level 1 Level 1 (5 points)
    but when my current PC won't charge the iPad, my only options are to buy a high powered USB 2.0 or a normal 3.0 card. I'd think, if its compatible, I should buy the 3.0 just so its more future proof.
  • B0b Level 2 Level 2 (245 points)
    the problem is not the charging its the message saying it is not charging.

    0.61 amps into the ipad does not flip the message from not charging to charging.

    I have no idea what the trigger point is.

    Isn't the USB 3 socket totally different ?

    Where is the battery current charging app - you software people
  • spald Level 1 Level 1 (5 points)
    Just an update:
    Since this thread, I've tried using both an addon USB 3.0 card (with power boost) and a built in USB 3.0 motherboard. Both times the iPad claims it's not charging when plugged in but it's definitely still is. I'd say it's about 1.5x faster than standard USB 2.
    From what I've read, the iPad doesn't claim to be charging unless connected to at least 2.1 Amps. Because USB 3.0 is only 0.9 Amps, the charging icon isn't triggered. I'm not sure how new Apple computers trigger the charging icon though because I very much doubt they have USB with that much current. I can only imagine the iPad recognizes the computer is made by Apple so artificially triggers it (even though it probably charges at the same rate).
  • Sethlution Level 1 Level 1 (0 points)

    Well I have the new Macbook Pro 2012 with USB 3.0 port, and I can confirmed you that the iPad does say that it is charging when plugged in.

  • Tony O. Level 1 Level 1 (0 points)

    My new iPad 3rd gen charges just fine when I plug it into a USB 3.0 port on my GA-Z68X-UD3H-B3 motherboard.