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  1.    #1  
    My laptop (a Thinkpad) has an "always on USB" port, but it doesn't seem to actually charge my Treo Pro. There is a bit of power being delivered, since the charge light comes on, but it's not enough.

    I'm wondering if the Palm USB-to-microUSB cable might be making the phone think that the USB port is unable to source enough current to charge.

    Has anybody been able to get this to work?
  2. #2  
    If you have the USB plugged into a computer that is not turned it, it will NOT charge the phone.

    The Treo Pro uses USB voltage or logic sensing to activate charging. What that means is one of two things:

    1) The Treo Pro must be connected to a computer that communicates properly to the phone that, it is indeed, connected to a computer with powered USB ports. The Treo Pro, once acknowledged into the system as a valid device, will then switch itself into charge mode.


    2) The proper voltage must be applied to D+ and D- (Data+ and Data-) pins. Once the proper voltage is sensed, the Treo Pro will switch itself into charge mode. For many devices there are 2 available levels of charge - around 350mv draw and high draw (up to 1A depending upon design) - and that is sensed by the voltage and resistance levels across ground on D+ and D-

    This is not unusual, many modern USB-charging devices work like this. The Apple iPod and iPhone, for example, work this way. Read about the D+ and D- voltage situation at

    How USB chargers work so that device knows to draw 500mA? - Page 2 - iLounge Forums

    When your computer is turned off it still may be providing 500mv (I would expect, that's "full" USB charging output as per standards) but it is NOT providing either clause (1) or (2) to the phone. So, the phone does not kick into "true" charge mode, it only stays in low-power "sustained trickle" mode. On one of my USB charger, that "sustained trickle" mode is enough to keep the battery from draining flat, but not enough to actually recharge the battery.

    My belief is that this cable may solve your problems

    Rocketfish™ Mobile - USB Charging Cable - RF-CA1MR

    This is the cable I use to enable a Belkin dual-output USB charger to recharge my Treo Pro - without this cable, the phone stays in "trickle charge" mode.

    HOWEVER...I am **NOT** sure what happens when you actually turn on a computer with that cable plugged into one of the active ports. Can the computer handle the D+/D- connection or does it freak out the computer...or worse? (kaBLOOEY??!) o_O Maybe check if you are going to use that cable - I've never used it plugged into a computer, only a non-logic powered USB port.
  3. #3  
    I'm on a Thinkpad Edge, and I had some problems first getting the "Always on USB" to work.

    First, make sure you have it enabled in the BIOS.

    Second, when you're in Windows, get into the Power Manager from Lenovo, and under Global Power Settings, enable the always on USB, and have it on "iPod or iPhone digital devices"

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