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Voltage of the ASUS Transformer 300

Discussion in 'Android Devices' started by pengyou, Jun 29, 2013.

  1. pengyou

    pengyou Well-Known Member
    Thread Starter

    I have read different things from different websites - one said that it takes 15v from the adapter and another 12v. Which one is right? Just to make sure, I am talking about the one that has the detachable keyboard with, I believe, a battery also built into the keyboard (but I could be wrong about this). I have not bought it yet but hope to in the next 2 weeks. I am planning some long train trips in the next 18 months and would like to find/make an external battery that is approximately the same length and width as the tablet that will power the tablet for about 20 hours.

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  2. heat57

    heat57 Android Enthusiast

    5-15V and 2-1.2A - this is directly taken from the charger
  3. peterc10

    peterc10 Android Enthusiast

    Charger is 15V. The keyboard does have a separate battery. However the combination of tablet and keyboard batteries won't last for 20 hours of use.
  4. wetbiker7

    wetbiker7 Extreme Android User

    Pretty sure specs say 12 for the tablet with an additional 5 with the dock. ROMs along with some apps play a huge part in the battery consumption too.
  5. peterc10

    peterc10 Android Enthusiast

    That may be what they say but I have never got anything like that when in actual real use, for example running a day long powerpoint presentation. Its the screen that really sucks out the battery I think.
  6. wetbiker7

    wetbiker7 Extreme Android User

    Yeah. Those specs are for normal use. Running it all day or running specialized apps like Powerpoint will def run it down quicker.

    I can watch several movies while running CM10 and my battery starts getting pretty low. On the other hand, I can run CleanROM and watch 4 movies and still have plenty of battery left. This is w/o the dock attached of course. If you are connecting via the HDMI output to another screen, the tablet screen will stay on with some ROMs or apps. I recommend turning the brightness down on the tablet. It will not affect the screen you are transmitting to. Either that or get an app from Play or the one over at XDA that disables the screen when an HDMI connection is made. That will help save a lot of the battery. :D

    There are a lot of tweaks that you can play with that will allow longer battery life too. ;) XDA has a wealth of knowledge on this tablet.
  7. peterc10

    peterc10 Android Enthusiast

    Wetbiker, I am not complaining about the life I get out the thing. In reality whenever I am running training seminars (3 to 6 times per month) I have it plugged in to the mains, so have no real problem.

    And I want the tablet screen on, and bright, as well as the projector so that I can glance down and see where I am without turning my back on the delegates to see what is on the screen. Powerpoint is there for the presenter - not the delegates!

    However I am sure the OP could get 20 hours of intermittent use easily, as long as he does not expect to have the screen on that length of time. And certainly turning the brightness down would help as well.
  8. wetbiker7

    wetbiker7 Extreme Android User

    LOL! Why in the world do you think I thought you were complaining? I didn't. In fact, I just thought we were discussing the battery life of the tablet. If I thought you were complaining, I would have told you to sell the tablet. :D:p

    And you are absolutely correct in the post earlier when you said you thought it was the screen that sucked the power out of the battery too. The screen on the TF300 is the main culprit for battery drain. That and a overclocked kernel.

    Overall, the TF300 gets good battery life IMO. ;)
  9. pengyou

    pengyou Well-Known Member
    Thread Starter

    thanks! WhenvI am on a long trip I cause a massive battery drain with my old notebook, often using an hd webcam to record the scenary while watching a dvd and powering a 3g modem to chat...that is why I am looking at custom battery!
    i plan to go to Tibet next summer which is a 55 hour train ride.....in past trips i have sometimes been able to do live streaming but I am not sure about on the way to Tibet
  10. wetbiker7

    wetbiker7 Extreme Android User

    External battery packs are a good option. There are all sizes on the market to choose from too. If you know you are going to be spending a lot of time on it and are going to be away from a charging source, the external battery pack is a good choice to consider.

    Going to Tibet huh? Lucky you!! :D:D
  11. LoneWolffe

    LoneWolffe Newbie

    Just wanted to put in something I learned from today's trip to Micro Center. The stock charger does indeed charge at 15V 1.2A if you connect it to the dock. If you connected the charger to the tablet alone, it would switch to 5V 2A.

    Here's where it gets sticky: plug in a 5V 2.1A charger to the dock and it bypasses the dock to charge only the tablet. It also seems to drain the dock attempting to charge this way. I'm not sure what would happen if the dock was already dead, though. It would probably still charge the tablet, but do nothing to the dock.

    The thing is, the dock needs 15V to charge it, otherwise it could never be able to feed the tablet, which runs at, what, 4.5V? I think any backup power solution needs to take into account the two voltages, or disconnect the dock once it's dead and charge the tablet with your 5V backup.

    "There's no such thing as a fool-proof system. Someone will make a better fool, tomorrow."
  12. peterc10

    peterc10 Android Enthusiast

    I think Micro Center have got it wrong.

    AFAIK when you plug into either dock or tablet it requires (and gets from the Asus charger) 15v to properly charge them. Try using the Asus lead in an ordinary USB 5V charger or your PC USB port and see how long it takes to charge the tablet. Last time I did it was over 30 hours with the screen off. With the screen on the charge level did not move at all.

    The dock uses very little power in itself. It is the tablet (and especially the screen) that takes the most power.
  13. LoneWolffe

    LoneWolffe Newbie

    Well, iOBit MobileCare tells me my tablet battery is running 4.xV, so charging off a 5V power supply like my laptop, is fine, but that will not charge the dock. Gonna check to see what the charge time is when I plug in to my car charger tomorrow and get back.
  14. peterc10

    peterc10 Android Enthusiast

    Its not what the battery is running at that is important it is the amount of power you have to put into what is a large capacity battery (by USB standards). The easiest way to check is just to plug the Asus lead into a standard 5v USB wall adapter.

    I have checked the manual and it definitely says that both the tablet and keyboard take 15V 1.2A. If you want to charge through the USB port of your PC (which provides 5V) the manual says you should switch off the tablet and it will take longer to charge.
  15. LoneWolffe

    LoneWolffe Newbie

    yep, you're right. my mouth is full and rightfully footed.

    attempted to charge on a 5V 2.1A car-usb charger and got nothing.

ASUS Transformer Pad 300 Forum

The ASUS Transformer Pad 300 release date was April 2012. Features and Specs include a 10.1" inch screen, 8MP camera, 1GB RAM, and Nvidia Tegra 3 T30L processor.

April 2012
Release Date

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