Retina MBP - how do I increase USB power output?

Discussion in 'MacBook Pro' started by Xcelerate, Jul 12, 2012.

  1. Xcelerate macrumors regular

    Jul 11, 2008
    My RMBP is adding energy to my phone at a rate slower than the phone is using it, and thus it eventually runs out of battery. Is there a setting somewhere to boost this output? Or maybe a program to do this?

    (In case you're wondering, there's no hardware defects -- already tested everything.)
  2. mohsy90 macrumors 65816


    Feb 4, 2011
    New York
    Umm, I don't think thats possible. Looks like theres something wrong with your iPhone battery. Battery shouldn't be losing more charge than it's gaining while plugged in....unless you got the speakers on high and are listening to music.

    Edit: Are you charging an iPhone?
  3. NewbieCanada macrumors 68030

    Oct 9, 2007
    Is your phone an iPhone? Does it charge properly with the charger or connected to another computer? My rMBP charges my iPhone quite well.
  4. pgiguere1 macrumors 68020


    May 28, 2009
    Montreal, Canada
    It should already be powerful enough to charge any phone while using it, like any recent Mac. Either your USB ports or your phone have a problem.

    If it was a 3rd-gen iPad running a 3D game that would be possible but for any smartphone I don't see how it would.
  5. sweetbrat macrumors 65816


    Jun 17, 2009
    Redford, MI
    If you're doing something very intensive with your phone (playing a graphics-heavy game, for instance) I wouldn't be surprised if the phone is using more power than it's gaining while charging. Is that the case, or is it somehow losing charge while it's plugged in and not being used? In any case, trying to increase the output of your USB port sounds like a good way to damage your computer...and your phone.
  6. sammich macrumors 601


    Sep 26, 2006
    Are you using a 3rd party cable that might be too long?

    You can check the power the phone is drawing by opening System Profiler. Click the Apple at the top left, hold the option/alt key and click 'System Profiler'.

    in the new window, find 'USB' on the left list and then find your iPhone in the top right pane. In the detail below, it should say how man Amps it is drawing. Should be 500mA with 500mA extra current.
  7. Xcelerate thread starter macrumors regular

    Jul 11, 2008
    Charging an Android phone. It charges on my old 2008 Dell laptop as well as through the wall outlet. But my guess is that the new RMBP puts out very slightly less power than my old laptop did.

    (In other words:

    With old laptop it charges slowly
    With RMBP it loses energy slowly
    With no charging it loses energy at the normal rate
    And wall outlet it charges quickly.)


    Yeah, that's what's happening. I'm using my phone as a Wifi hotspot. But even without using it as a hotspot, it charges very slowly (hence why I was wondering if I could increase the power output).

    Sammich, here's what I got from the system profile:

    LG Android USB Device:

    Product ID: 0x61a6
    Vendor ID: 0x1004 (LG Electronics Inc.)
    Version: 1.00
    Serial Number: A00000288D002F
    Speed: Up to 480 Mb/sec
    Manufacturer: LG Electronics Inc.
    Location ID: 0x1d110000 / 7
    Current Available (mA): 500
    Current Required (mA): 400
  8. sammich macrumors 601


    Sep 26, 2006
    All recent (not sure how far back) Apple computers have high powered USB ports that can output 2.1A. That's the same output as the iPad wall charger. It could be a change in the charging logic between OS X and Windows or something (no idea). Won't be able to see anything until you can get the power supplied to the phone via USB on both machines.
  9. stevelam macrumors 65816

    Nov 4, 2010
    That's what you get for having a ****** android phone. I used to have the Samsung s2 and it charged about 5x slower than my iPhone 4s when plugged into USB of any of my computers. Who knows why.
  10. zerotiu macrumors regular

    Jun 12, 2012
    Irrelevant. My motorola milestones can be charged normally. I personally don't like to charge my mobile phones on a laptop.
  11. 01mggt macrumors 6502

    Jun 23, 2010
    I seem to remember hearing that USB 3.0 ports are actually more powerful than USB 2. But of course it still will be no match for a wall charger. Ther is a very good chance that the app you are using to tether is coded badly and causing a big battery drain. At the least, the phone should hold it's current charge while running a wifi hotspot. My iPhone will mantain current charge even running GPS and plugged into a USB cigg lighter adaptor. Maybe try another tethering app. I have tethered my iphone as a wifi hotspot and it charged fine off my 2008 macbook.
  12. iMacDragon macrumors 68000


    Oct 18, 2008
    Only if the device requests the extra power in apple way. an android phone probably does not do this, and only gets the normal 500mA.

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