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  1. eps's Avatar
    The Google supplied charging cable charges my N7 at more than twice the rate of a generic 3rd party cable I have long used for my GN.

    I noticed that the metallic connector on the Google cable is slightly longer than the generic cable.

    Could this be the cause of slow charging with the generic cable?
    Is Google shipping a proprietary/non-standard cable with the N7?
    skyrail likes this.
    07-18-2012 06:26 PM
  2. Ry's Avatar
    I haven't seen the cable that ships with the Nexus 7, but is it a straight power cable or is it a USB power adapter where you still need plug in the micro USB cable into it?

    Sent from my DROID BIONIC using Android Central Forums
    07-18-2012 06:34 PM
  3. stkorn97's Avatar
    Usb adapter. And I've used 2 different cables without any issues so far.
    07-18-2012 06:45 PM
  4. TheStereoMike's Avatar
    07-18-2012 06:54 PM
  5. eps's Avatar
    Usb adapter. And I've used 2 different cables without any issues so far.
    Have you measured the charging speeds and compared with the supplied cable?

    Is the metallic part of the google supplied microUSB cable end a bit longer than your 3rd party cables?
    07-18-2012 07:57 PM
  6. uM-elo's Avatar
    Besides a slower charge or not charging at all, the third party chargers won't harm the device/battery, right?

    I've heard that the different voltage or something can be problematic, is that true?
    07-18-2012 07:58 PM
  7. Flatland2D's Avatar
    I noticed after plugging in a different USB charger for the first charge that it wasn't charging. It turns out the silver colored plastic bezel extends beyond the metal of the USB port. I think this is one reason why the supplied cable has a longer metal part on the micro USB side. I was able to get my other charger to work, but I had to make sure to really push it in all the way to make good contact.

    Sent from my Nexus 7 using Tapatalk 2
    07-18-2012 08:06 PM
  8. dpridgen's Avatar
    The nexus 7 charger puts out 2amps @5 volts. Most of the generic or other brand chargers range from .5ams to about 1 amp. The cable itself won't make any difference, you can use any USB to micro usb cable you like, but you will want to use the charger that came with the Nexus 7 or find one that can put out at least 2 amps @5 volts. This one from monoprice will work, it puts out 2.1 amps. 2.1 amp usb wall charger.
    07-18-2012 08:09 PM
  9. eps's Avatar
    The nexus 7 charger puts out 2amps @5 volts. Most of the generic or other brand chargers range from .5ams to about 1 amp. The cable itself won't make any difference, you can use any USB to micro usb cable you like, but you will want to use the charger that came with the Nexus 7 or find one that can put out at least 2 amps @5 volts. This one from monoprice will work, it puts out 2.1 amps. 2.1 amp usb wall charger.
    The cable itself does make a difference in my case. My monoprice cable will not engage the microUSB port snuggly due partial obstruction by the silver bezel. It remains wobbly regardless of how hard one tries to push it in since the plastic hood of the cable butts up against the silver bezel, preventing the metal contact from fully penetrating the port. It still "charges" with the monoprice but very slowly.... roughly half the speed of the OEM cable.
    07-18-2012 11:04 PM
  10. dpridgen's Avatar
    The cable itself does make a difference in my case. My monoprice cable will not engage the microUSB port snuggly due partial obstruction by the silver bezel. It remains wobbly regardless of how hard one tries to push it in since the plastic hood of the cable butts up against the silver bezel, preventing the metal contact from fully penetrating the port. It still "charges" with the monoprice but very slowly.... roughly half the speed of the OEM cable.
    Yes, you are correct, I should have said that the cable should not make much difference since the pin-outs are standardized, however, the connector length and clearance could make a difference in whether or not you make good contact with the receiver pins
    Ry likes this.
    07-18-2012 11:28 PM
  11. biogon's Avatar
    I'll have to check when I get home, but it didn't look like the N7 uses the same "extra-long micro USB" that the Nook Color/Tablet used -- there were extra pinouts to carry the additional power, I think.

    It would fast-charge only with the special $30 Nook USB cable. ::rolleyes::
    07-19-2012 09:43 AM
  12. cohoman's Avatar
    The nexus 7 charger puts out 2amps @5 volts. Most of the generic or other brand chargers range from .5ams to about 1 amp. The cable itself won't make any difference, you can use any USB to micro usb cable you like, but you will want to use the charger that came with the Nexus 7 or find one that can put out at least 2 amps @5 volts. This one from monoprice will work, it puts out 2.1 amps. 2.1 amp usb wall charger.
    What's the amps coming from a laptop or PC USB port? I wonder now of that is sufficient to charge the N7.

    Sent from my Nexus 7 using Android Central Forums
    07-19-2012 09:52 AM
  13. Flatland2D's Avatar
    Computer USB ports are regulated to 500 mA.

    Sent from my SCH-I535 using Tapatalk 2
    07-19-2012 10:51 AM
  14. stkorn97's Avatar
    I cut some of the rubber around connection of a cable that wasn't working before, it had the same charge time remaining as standard cable according to battery app. Connector length could be the issue.
    07-19-2012 11:04 AM
  15. pokingmon's Avatar
    I have a microUSB cable that came with a wireless keyboard. It's labeled with a sticker that says it's for charging only and won't provide a data connection. Not only does it provide a data connection, but it also charges my N7 at a speedy enough rate that I can only assume is around the same speed as the cable that came with it. It's connected to the supplied charger that came with it though. Maybe this cable is similar to the included one and has the longer tab?

    ALSO: my girlfriend's DROID RAZR charger (with 2 USB ports) charges it, as well as my single USB port Galaxy S2 charger. My cellphone/tablet stand/hub I got from Target does NOT charge my N7, nor does my Belkin 3 outlet mini surge protector with USB ports. (unless of course I plug the included charger to one of the power outlets.
    07-19-2012 03:44 PM
  16. YAYTech's Avatar
    The USB cable from my Droid RAZR charges my Nexus 7, though I don't know if the cable affects the rate. The charger from my OG Droid works, as does the charger for my RAZR, but they would definitely affect the charging rate, as they're both lower amperage chargers.

    I have an aftermarket microUSB cable that has caused me some grief before - the microUSB head receeds just a bit into the plastic behind it. When it does this, the USB connection seems to work fine, but it doesn't charge. If I grab the end and slide it out, and carefully insert it into a device, then it charges (not tested on the N7, but on my RAZR). Something you might look at.
    07-19-2012 09:52 PM
  17. pageo's Avatar
    Nook Color uUSB plug is longer than N7 uUSB plug.

    Here's desc of NC charging design, perhaps googke/asus did something similar on N7?

    Nook Color charger uses special micro-USB connecto... - Barnes & Noble Book Clubs
    07-20-2012 02:34 PM
  18. biogon's Avatar
    Yeah, I noted that above.

    I went home and checked, it looks like a regular-length micro USB though.

    So I don't think that's it.

    Annoying.

    Nook Color uUSB plug is longer than N7 uUSB plug.

    Here's desc of NC charging design, perhaps googke/asus did something similar on N7?

    Nook Color charger uses special micro-USB connecto... - Barnes & Noble Book Clubs
    07-20-2012 02:37 PM
  19. eps's Avatar
    Graph showing reduced charging rate when changed from OEM to 3rd party microUSB cable.
    biogon and skyrail like this.
    07-22-2012 01:50 PM
  20. ace518's Avatar
    Actually just got a couple of these to use charging the nexus 7. Unless I'm having an issue with my cables (they work if i plug into the PC) I'm not getting the nexus 7 to charge off of this. It works with other devices. Very odd. I will check further into it tonight after I get home from work and update. But, has anyone else had any issues with this wall charger?
    09-12-2012 03:30 PM
  21. YAYTech's Avatar
    Actually just got a couple of these to use charging the nexus 7. Unless I'm having an issue with my cables (they work if i plug into the PC) I'm not getting the nexus 7 to charge off of this. It works with other devices. Very odd. I will check further into it tonight after I get home from work and update. But, has anyone else had any issues with this wall charger?
    A couple of these... what? Aftermarket cables?

    It's faulty logic to say "aftermarket cables are bad", because not all aftermarket cables are made the same. Some will work just as well as OEM, some won't work at all, some will work at a reduced rate. If you want to be absolutely sure a cable will work like it should, get an OEM cable, but considering the savings potential of aftermarket cables, I would go with one known to work as well as OEM. Let others do the trial & error, then get what's confirmed to work properly for less money than OEM. For example, I've noticed no difference in using the cable that originally came with my Droid Razr. (The charger that came with the Razr is another story, since it has a lower amperage.)
    09-13-2012 03:07 PM
  22. ChromeJob's Avatar
    I've measured the millliamps (as indicated in Battery Monitor Widget Pro) using a sturdy AmazonBasics cable (4') and the supplied one, both with the Asus charger, and the supplied one gives more current. I couldn't tell you why, my electronics training tells me that there shouldnt be that much a difference in the conductivity of a cable.

    The supplied Asus cable is a sync & charge cable, not charge-only. It's less thick/sturdy than the AmazonBasics cable.

    I've found the same with my HTC U250 charger and the T500 cable. The T500 uses the ExtMicroUSB connector that HTC put on a few devices, but only has the 5 conventional pins, not 12 like the HDMI out adapter. The HTC cable just seems to provide more current.

    At this point, until someone tells me something about wires and conductors that I don't know, I chalk it up to magic pixie dust.
    09-14-2012 08:35 AM
  23. velomichael's Avatar
    Most all the theories offered in this thread are wrong. The internal connections of USB charging cables differs even among cables with the exact same connectors. Likewise there are more differences between chargers than just current output.

    The reason some companies deviate from the standard USB spec is to allow the device to detect a >500ma power source for faster charging. Apple, Samsung, Blackberry, and others, also use nonstandard USB for faster charging. The Nexus 7 is in good company.

    Without the special pin out, jumpers, charger configuration, etc. the device falls back to 500ma charging as that's the max most PC's allow.

    I am sure there will be cheap USB third party cables that work if there are not some already.
    09-14-2012 06:58 PM
  24. ChromeJob's Avatar
    8It's not the cables, usually, it's the chargers. If the D+ and D- lines are shorted, the device recognizes the USB port as charging only, and will draw a higher current. Many cheap chargers don't have those shorted, so a device, when plugged in, will see it as a USB port, which is capped at 500mA, and only draw that much. Amazon is awash with reviewers scratching their heads and wondering why their "5VDC 1A" charger doesn't charge any faster than plugging the device into their computer -- that's why.

    Apple, of course is special. They have reference voltages on D+ and D- (2.0V and 2.8V I think), which their devices look for. If you boot an iPod into the diagnostic menu, you can see it measuring these. Hence, some chargers now offer "Apple and non-Apple" ports. I've got one coming tomorrow from Amazon....

    There are a few cables which have the data lines shorted out, I received one with a Duracell home/car combo charger. But it didn't support very much current no matter what I plugged it into, and it sits in a drawer at work.

    My point is that on a charger that is pinned out to identify itself as an AC charger (D+ and D- shorted), with two cables that are pinned out the same (for data sync and charging), the device will draw more on one cable than another. Same charger, same type of cable. Again, I spent several years working in military avionics (analog and digital equipment), and the best that I can figure is that, perhaps, some cables have way more braided wire in them, allowing a slightly higher current flow. In a 3' or 4' cable, though, that really surprises me. Perhaps the charging circuits of these devices recognize that. I've seen this repeated many times with my HTC Amaze with the oem charger and cable, a smooth bell curve as the charging circuit tapers off the current as the battery nears full. The initial high voltage, and even sometimes the gradual tapering off, aren't repeated with some third party chargers and cables. For this reason, I bought two more HTC T500 cables and chargers (oh, HTC will send you "replacements" as a courtesy if you call them and ask nicely) so I could get a faster charge in various locations.





    EDIT : By the way, the blue line on the second image indicates the HTC Amaze thought it was plugged into an USB port, not an AC charger. And it drew power accordingly.
    09-14-2012 09:57 PM
  25. lmvine's Avatar
    09-18-2012 10:54 AM
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