Database Users

Charging from USB?

I keep getting a red X Through my battery when plugged into my laptop to charge, is this normal? I really dont want to plug into the wall to charge

Really hope this doesn't become the case and that it will charge off of any USB charger...in particular like the one in my car that accepts USB Devices.

My friend has a galaxy and has the same issue, idk if its our laptops or what

Okay this has been address. please search but ill answer for you.
This device uses 5v 2a to charge. Hence the wall unit. you computer is 5v 1a or 1.5a (its not enough)
The device will maintain and in some cases when screen off slowly charge when plugged into computer or usb adaptor with the red "x" through it.
you can find a usb adapter cable which has a switch to allow you to charge while connected to a computer. its a data and charge switch. search for it. i think its on ebay.
also you can find on amazon or google shopping wall chargers for the p1000 which work for like 8$

dsh897 said:
Okay this has been address. please search but ill answer for you.
This device uses 5v 2a to charge. Hence the wall unit. you computer is 5v 1a or 1.5a (its not enough)
The device will maintain and in some cases when screen off slowly charge when plugged into computer or usb adaptor with the red "x" through it.
you can find a usb adapter cable which has a switch to allow you to charge while connected to a computer. its a data and charge switch. search for it. i think its on ebay.
also you can find on amazon or google shopping wall chargers for the p1000 which work for like 8$
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thanks, and thats very disappointing

DroidHam said:
thanks, and thats very disappointing
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its not disappointing at all.what other tegra2 tablet can even trickle charge through USB 2.0?

madsquabbles said:
its not disappointing at all.what other tegra2 tablet can even trickle charge through USB 2.0?
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My xoom could.

DroidHam said:
My xoom could.
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my 4 didn't and neither does a bunch of other peoples xooms. even if it did it would only charge at the same rate as the gt10.1 charges - 5 watts. that's the max USB 2.0 spec.

It should be easily solved with a 2 x male 1 x female usb cable
http://ep.yimg.com/ca/I/yhst-19158458583166_2164_10126151

DroidHam said:
I keep getting a red X Through my battery when plugged into my laptop to charge, is this normal? I really dont want to plug into the wall to charge
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It charges through usb when the tab is powered off.

zaphyr said:
It should be easily solved with a 2 x male 1 x female usb cable
http://ep.yimg.com/ca/I/yhst-19158458583166_2164_10126151
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Where does one buy said cable?

hshah said:
Where does one buy said cable?
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Depends on your country I guess, I bought mine from Dustinhome.se:
http://www.dustinhome.se/pd_5010312807.aspx

Lou2serious said:
It charges through usb when the tab is powered off.
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even with it on it'll charge slowly.

Those double cables are cheap (around £3 in the UK) so I might pick up a couple of those and leave them at work and in the car

hshah said:
Where does one buy said cable?
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http://cgi.ebay.com/New-USB-2-0-Fem...871?pt=LH_DefaultDomain_0&hash=item27ba21e847

Having this Y-cable will also help with the fact that the USB cable that came with the tablet is so sort. I have a lot of 5V power supplies around but they are all from 50ma to 1a. Can't believe this thing needs to much power to charge, I would think that 1a would be enough just to maintain it when in use.

OK, I got a couple Y/Split cables and I still have red X when plugged into two USB ports, I even tried two ports that are on different controllers... as well as two USB3 ports in my laptop. I even tried my desktop. No luck.
Has anyone gotten this to work?

I posted in the accessories section about this subject, see here;
http://forum.xda-developers.com/showpost.php?p=14890063&postcount=16
and here;
http://forum.xda-developers.com/showpost.php?p=14922116&postcount=27

The red x will show up if you are charging with anything under 2A. If I remember correctly usb 1 puts out 100ma and usb 2 & 3 put out 500ma. Even with a Y adapter you will only get 1A. If the screen is off then you will charge the battery however with the screen on, you are using the same amount of power that the usb is providing. Therefore the x because the battery is not charging.
Sent from my GT-P7510 using XDA Premium App

ericlmccormick said:
The red x will show up if you are charging with anything under 2A. If I remember correctly usb 1 puts out 100ma and usb 2 & 3 put out 500ma.
Sent from my GT-P7510 using XDA Premium App
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With the adapter I posted about above, I never see the red x and I am charging off USB 2.
-EDIT-
To be clear, I am using a 10.1v not a 10.1 - there could be differences, but I doubt it.

Slightly better battery life.

So I realized that if I charge my phone using the USB ports on my laptop, the phones batter lasts much longer than if I charged it through the power outlet in the wall.
I didn't take any screenshots because I didn't think of it at the time, but through the laptop I got about 2 days and 14 hours with moderate use and I had 18% battery left.
Through the wall charger, I get about 18 hours with moderate use.
Can anyone else confirm?

Not sure, but i do feel that it charge slower on the USB port of my laptop. Maybe it have something to do with your theory.

Centranly!
USB port can give max 500mA but the wall charger can supply with 700mA (+40%!!!)

I have a charge-only cable that charges over my MBP's USB faster than any AC adapter I've tried. Charges last about the same regardless of power source though...
Sent from my MB860 using xda premium

emandt said:
Centranly!
USB port can give max 500mA but the wall charger can supply with 700mA (+40%!!!)
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USB 2.0 will provide up to 500mA while USB 3.0 can provide 800mA. Stock Atrix wall charger I have is 850mA.

How do you verify what mA you're using? Is there a good tool for that?

CaelanT said:
USB 2.0 will provide up to 500mA while USB 3.0 can provide 800mA. Stock Atrix wall charger I have is 850mA.
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IIRC, these are minimum specs for the standards. Could be wrong, but I believe that true output varies card to card/port to port.
Sent from my MB860 using xda premium

Plasmamuffins said:
So I realized that if I charge my phone using the USB ports on my laptop, the phones batter lasts much longer than if I charged it through the power outlet in the wall.
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I've heard this theory before, but didn't see noticeable difference on my phone to back this claim.

I do agree with OP that charging the phone connected to a laptop USB port would give longer battery life. I have noticed this on several occasions already. I also agree the charge process would be much slower. With my phone, with 5% charge or less, the battery icon randomly doesn't animate while being charged.
That a side, I'm also sure something is broken in Atrix design, be it hardware, battery, or both but something is not right. I can't even charge my phone from a power point with the supplied cable and the plug [UK].
I know Motorola won't admit neither fix this problem in Gingerbread but might do, quietly, in ICS. One other possibility I can think of is that the supplied plugs are the culprit.

Today i charged the phone from my laptop, and im not feeling any difference at all. Its discharging at my usual pace. :/
Sent from my MB860 using XDA

Furthermore to my previous post, I have finally found the opportunity to test my phone with a Blackberry charger and it started charging the phone from the power point. That means the Motorola UK plugs I have are broken.
I'm arranging to purchase a Blackberry charger now. Don't want waste my time and money with Motorola anymore.

Need help. My Transformer won't charge anymore

Hi,
I hope someone can help me. My Transformer doesn't charge anymore since yesterday.
Tablet was around 10% when i put the charger in, but the message 'Connect your charger'doesn't go away.
Strange thing is that whenever i plug it in and TF is off, it will turn on, so I guess the wall charger and cable are functioning.
Also when connecting it to my PC I can sync.
I've tried already all the solutions i could find online:
- put the wall charger in the freezer --> didn't work
- cold boot --> didn't work
- factory reset --> didn't work
- tried a different wall charger and connected the wire to a portable battery --> didn't work
- flashed the ROM again --> didn't work
The only way now i have for charging my TF is by USB (connected to PC while turned off). It will charge this way but it takes about 3 hours to get 10% charge from this.
Anyone had this happen already before?

So you tried multiple Asus wall chargers? with no luck? A standard USB charger will not work as those have an output voltage of 5+ when the tf requires 12+.
Sounds like you have a bad charger, you can join the club of thousands... It is a very common issue and not always resolved by the freezer or fiddling trick. If you are able to trickle charge via a PC connection then your cable and tf should be good.
Sent from my SAMSUNG-SGH-I997 using XDA

Link for another discussion where I listed an alternate charger
http://forum.xda-developers.com/showthread.php?p=23917818
It really is heads and tails better than the Asus one
Sent from my SAMSUNG-SGH-I997 using XDA

theraffman said:
So you tried multiple Asus wall chargers? with no luck? A standard USB charger will not work as those have an output voltage of 5+ when the tf requires 12+.
Sounds like you have a bad charger, you can join the club of thousands... It is a very common issue and not always resolved by the freezer or fiddling trick. If you are able to trickle charge via a PC connection then your cable and tf should be good.
Sent from my SAMSUNG-SGH-I997 using XDA
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Click to collapse
No, I tried with a different wall charger (from Motorola). I don't think it's the wall charger though, but to make sure I wil connect it to a phone and check if it's working.
It just feels like the cable and wall charger is working as it should (tablet powers up or screen turns on when I plug it in), but the tablet refuses to charge.
Could it be the pins?
Sent from my GT-I9100 using xda premium

And the motorola USB charger puts out at least 12 volts and not just 5. Is it the wall charger for the zoom? I was UN aware that the zoom used a USB type charger (similar to the tf).
Once again, you can't use just any USB wall charger for the tf... 99% of chargers put out the standard 5 volts which is enough to trickle charge a tf and to slightly charge it in done cases when powered down. I am only adamant about this this because I have sewn this post a hundred times, and 99 of those times it was the charger... Many people don't realize the tf USB charger is very coherent then what most folks are accustom to, even though it looks and acts similar to others.
The only way to confirm is to find someone who has a tf and borrow their charger, our go to radio shack and buy the charger I listed... Which you should do any ways because it's is way way better, my charging cord over all length is 10ft. Beats the hell out of the 2 or 3 you normally would have.
Sent from my SAMSUNG-SGH-I997 using XDA

theraffman said:
And the motorola USB charger puts out at least 12 volts and not just 5. Is it the wall charger for the zoom? I was UN aware that the zoom used a USB type charger (similar to the tf).
Once again, you can't use just any USB wall charger for the tf... 99% of chargers put out the standard 5 volts which is enough to trickle charge a tf and to slightly charge it in done cases when powered down. I am only adamant about this this because I have sewn this post a hundred times, and 99 of those times it was the charger... Many people don't realize the tf USB charger is very coherent then what most folks are accustom to, even though it looks and acts similar to others.
The only way to confirm is to find someone who has a tf and borrow their charger, our go to radio shack and buy the charger I listed... Which you should do any ways because it's is way way better, my charging cord over all length is 10ft. Beats the hell out of the 2 or 3 you normally would have.
Sent from my SAMSUNG-SGH-I997 using XDA
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Thanks for your replies.
You're right, the Motorola wall charger is only 5v output. It was the one I got with the Milestone. I do start to believe it might be the wall charger after all now.
Unfortunately I don't know anyone else with a TF (anyone reading this lives in Ghent, Belgium with aTF?). Radio Shack isn't an option either since I live in Belgium, but I'll try to find overhere or online.
Anyway, appreciate your help. Might try the freezer thing again in the meantime... you never know.
When you connect your TF to a pc on a usb 3.0 port, should you be able to see the TF charging? Or no way to get more the 5v from this too?
Sent from my Transformer TF101 using xda premium

do u know anyone with an ipad? sure the wall chargers are 15w out and should do the trick.

Alta1r said:
When you connect your TF to a pc on a usb 3.0 port, should you be able to see the TF charging? Or no way to get more the 5v from this too?
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USB is 5V. No exceptions.
What you can do is build your own PC charger, like the one in my sig.

scottyf79 said:
do u know anyone with an ipad? sure the wall chargers are 15w out and should do the trick.
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Cheers man, my colleague has an ipad. Will ask him to bring his wall charger.

Goatshocker said:
USB is 5V. No exceptions.
What you can do is build your own PC charger, like the one in my sig.
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Click to collapse
I might try that, but only if I have no other choice (i fear i'll blow up my TF while doing that).

usb chargers are 5v only and will charge but take all day. The TF charger uses the physical usb plug to do double duty. transfer data via usb and charge device using 15v when the charger block sees a gnd signal on pin 7. Charging is not usb. There are several after market chargers that have variable output voltages and an asst of connectors (usb being one) best one is dynex video charger. Also you should not attempt to flash a ROM with 10% charge as you could get stuck in the middle of a charge and have problems.

Well, it was the wall charger after all. Went out to buy a power adapter with 12v and 1000mA output and the tablet is charging again. Many thanks to all people that replied and tried to help me.
For your info: ipad or galaxy wall charger aren't working with our TF's, they both only have an out put of 5v.
Sent from my Transformer TF101 using xda premium

Alta1r said:
Well, it was the wall charger after all. Went out to buy a power adapter with 12v and 1000mA output and the tablet is charging again. Many thanks to all people that replied and tried to help me.
For your info: ipad or galaxy wall charger aren't working with our TF's, they both only have an out put of 5v.
Sent from my Transformer TF101 using xda premium
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Never allow your charge level fall below 30% because it will cause your charger to overheat and eventually stop working.

Nexus 7 Battery recharging method

Hello everyone, I just bought my Nexus 7 from Ebay (from an UK seller) but the wall charger for UK doesn't work here in my country so:
Can I use the PC to recharge it trough micro USB?
If I can recharge it in this way, recharging needs more time?

sorcio46 said:
Hello everyone, I just bought my Nexus 7 from Ebay (from an UK seller) but the wall charger for UK doesn't work here in my country so:
Can I use the PC to recharge it trough micro USB?
If I can recharge it in this way, recharging needs more time?
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Click to collapse
1. Yes, you can recharge over your PC USB
2. Yes, unless you have high output USB ports (default charger is 2A, most PC USB ports are 500mA to 900mA) so the charge time is longer.

goofball2k said:
1. Yes, you can recharge over your PC USB
2. Yes, unless you have high output USB ports (default charger is 2A, most PC USB ports are 500mA to 900mA) so the charge time is longer.
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Thanks,
this feature of my motherboard can help me in some ways? http://www.asrock.com/feature/appcharger/index.asp

You can only charge it if the screen is off or better yet if the device is off. Give it 12 hours for a full charge over standard 500mA USB.
Sent from my Nexus 7 using xda app-developers app

Yeah, if you use your nexus 7 while its plugged in to the USB port of your PC you will loose battery, in Particularly if you are gaming lol. Mine when down from of 7% in 30 mins. Use a wall charger.

redmonke255 said:
You can only charge it if the screen is off or better yet if the device is off. Give it 12 hours for a full charge over standard 500mA USB.
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Is it really this kind of slow?
fredyboy said:
Yeah, if you use your nexus 7 while its plugged in to the USB port of your PC you will loose battery, in Particularly if you are gaming lol. Mine when down from of 7% in 30 mins. Use a wall charger.
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As I saild in the OP i cannot use that wall charger in my country

Surely you could buy a separate microUSB wall charger from somewhere in your country.

I've been using HTC and galaxy s2 charge. Had no problems and charging is very fast. Went from 30 to full in 2.5 hours
Sent from my Nexus 7 using Tapatalk 2

desiresiscool said:
I've been using HTC and galaxy s2 charge. Had no problems and charging is very fast. Went from 30 to full in 2.5 hours
Sent from my Nexus 7 using Tapatalk 2
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Thanks for the answer I will use the one of my note

You could always use a power adapter as well adapt from us plugs to your countries plugs

Chargers....
A Standard AC USB Charger will do the job in most cases, I'm using a powered Logitech USB Hub that just charges my BT Headset, my Galaxy S2 and now my Nexus 7.
If you want some faster charging times a Standard iPad USB charger plug should work, (they're rated for 2.1A instead of the 1A of the Normal iPhone chargers) just use the MicroUSB cable that you have and plug it in.
In response to your App Charger driver, it's probably that AsRock has built their USB ports and plumbed it in to higher +5V Amp line on your motherboard ie. they can deliver more power than the Standard USB Spec (500mA), I'm guessing at their 40% faster claim the port is delivering 900mA.
Good luck! The Nexus 7 has a 4326 mAh battery (ie 2.6x bigger than the Galaxy S2 Battery) so it'll take much longer to fill than all the Smartphones

car charger

Any idea why I can't seem to charge my Nexus 7 with my car charger?
i have both a generic Micro USB charger and I have one of the dual USB ports that you put into the cigarette lighter. It wont even acknowledge that I have plugged anything into it.
i have used the USB port to charge MANY different cell phones my old Dell Streak 7 and even a friends iPad.
Any ideas?

joeclark said:
Any idea why I can't seem to charge my Nexus 7 with my car charger?
i have both a generic Micro USB charger and I have one of the dual USB ports that you put into the cigarette lighter. It wont even acknowledge that I have plugged anything into it.
i have used the USB port to charge MANY different cell phones my old Dell Streak 7 and even a friends iPad.
Any ideas?
Click to expand...
Click to collapse
I think the N7 needs 2A to charge. a single USB is 500 mA and the dual 1A, so I don't think there's enough power.
Also check if the output of your microUSB cigarette charger is 2A

zaphyr said:
I think the N7 needs 2A to charge. a single USB is 500 mA and the dual 1A, so I don't think there's enough power.
Also check if the output of your microUSB cigarette charger is 2A
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Click to collapse
well i think that answers my question. thank you

This one will work: http://www.amazon.com/gp/product/B0090SVY3K/ref=oh_details_o02_s00_i00
It charges at the same rate as the stock AC charger.

The N7 is one picky device for charging. I have several chargers for the car that charge the iPad but not one will charge the N7. Same as AC chargers. This set works for me
http://www.amazon.com/dp/B008FF84K0/ref=pe_175190_21431760_M2T1_ST1_3p_dp_1

This is what I use and it works just fine. I use it to charge my N7, GNote, Nook Color or my grandsons IPhone and it works equally well on all of them.
BTW, it prime available if you are a member.

dparrothead1 said:
This is what I use and it works just fine. I use it to charge my N7, GNote, Nook Color or my grandsons IPhone and it works equally well on all of them. Very unobtrusive and I like the fact that the fuse is easily accessable.
http://www.amazon.com/Ultra-Compact...sr=8-2&keywords=ultra+compact+usb+car+charger
BTW, it prime available if you are a member.
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Click to collapse
That is exactly what I need to get.
Thank you.
Sent from my Nexus 7 using Tapatalk HD

It only charges via usb when the screen is off or when the device is off. Try plugging it in checking the battery % leave it awhile and then recheck the battery % you may find its gone up!
Sent from my GT-I9000 using xda app-developers app