Hey guys - I've been dealing with a Tab charging issue for a few days, and finally solved it... but I thought I'd post the problem and solution here in case it can save someone else a load of frustration if they run into the same problem.
From what I've read, we know that the Tab only draws .5A power from a USB socket, but that it draws ~2A from the wall, and that it knows the difference by testing for a short on the TX/RX USB data wires. (Correct me if I'm wrong on the details, but that's the general impression I've gotten.) We also know that the iPhone/iPad/iPod uses a pair of resistors instead (per the USB spec) to determine the current-delivery capability of the source. (I'm no EE, so I'm a little fuzzy on how that works from a technical perspective.)
So to set the stage: I had brought the USB cable for my Tab with me, but had neglected to grab the USB->outlet adapter for the mains. Similarly, a friend who was on vacation with us had forgotten the charging cable for his iPhone. Thinking I was killing two birds with one stone, I bought an aftermarket USB charging cable for the iPhone which had a separate USB->outlet adapter. His iPhone charged swimmingly, and when I charged my Tab overnight (screen off, starting at ~89% charge) using my cable and the aftermarket adapter, it worked flawlessly. No problem, great solution, or so it seemed...
...until I got home. Suddenly, my Tab wouldn't do more than a trickle charge - the same charge it gets when connected to the USB port on my laptop. (I could tell this was the case because of the small red 'x' next to the charging symbol in the battery icon - which I hadn't noticed while on vacation.) A 2.5-hour car trip using Navigator (screen on the whole time), even with the car charger connected, killed the battery completely. No matter what I did - shutting down apps, rebooting the device, resetting every option I could find - I could not get a fast charge to happen. Even leaving the device plugged in overnight resulted in *less* charge than what I started with if I didn't turn the screen off. I called T-mobile, talked to Samsung tech support twice... and all they could offer was to have me send the Tab back for replacement.
I was at a loss. I nearly did a hard reset in frustration, thinking I had screwed something up royally.
Then I saw the resistors in the pictures in this post:
http://forum.xda-developers.com/showthread.php?t=845844&page=3
and something clicked. I had been assuming that the *cables* were the difference between the iPhone and Tab chargers... but there isn't enough room for resistors in the cables! (Well technically, there is, but regardless...) The resistors must live somewhere else... and, I reasoned, that somewhere must be inside the USB->outlet adapter. So I pulled out the 'proper' Samsung adapter, plugged in the Tab, and voilà... a perfect fast charge.
So this is why the Tab won't charge with an iPod (or Sony-Ericsson, as it turns out) mains USB adapter OR USB-port car charger: the circuitry to let the device know it's capable of a full 2A delivery doesn't live in the Samsung cables; it's only present in the adapter. If that's not there, the device thinks it's connected via USB (and will, in fact, say "USB Connected" every time the charger is plugged in) and won't charge more than a trickle.
So that's my story, and hopefully it can save someone else some pain and frustration. Thanks for giving me the floor.
mattcelt said:
Hey guys - I've been dealing with a Tab charging issue for a few days, and finally solved it... but I thought I'd post the problem and solution here in case it can save someone else a load of frustration if they run into the same problem.
From what I've read, we know that the Tab only draws .5A power from a USB socket, but that it draws ~2A from the wall, and that it knows the difference by testing for a short on the TX/RX USB data wires. (Correct me if I'm wrong on the details, but that's the general impression I've gotten.) We also know that the iPhone/iPad/iPod uses a pair of resistors instead (per the USB spec) to determine the current-delivery capability of the source. (I'm no EE, so I'm a little fuzzy on how that works from a technical perspective.)
So to set the stage: I had brought the USB cable for my Tab with me, but had neglected to grab the USB->outlet adapter for the mains. Similarly, a friend who was on vacation with us had forgotten the charging cable for his iPhone. Thinking I was killing two birds with one stone, I bought an aftermarket USB charging cable for the iPhone which had a separate USB->outlet adapter. His iPhone charged swimmingly, and when I charged my Tab overnight (screen off, starting at ~89% charge) using my cable and the aftermarket adapter, it worked flawlessly. No problem, great solution, or so it seemed...
...until I got home. Suddenly, my Tab wouldn't do more than a trickle charge - the same charge it gets when connected to the USB port on my laptop. (I could tell this was the case because of the small red 'x' next to the charging symbol in the battery icon - which I hadn't noticed while on vacation.) A 2.5-hour car trip using Navigator (screen on the whole time), even with the car charger connected, killed the battery completely. No matter what I did - shutting down apps, rebooting the device, resetting every option I could find - I could not get a fast charge to happen. Even leaving the device plugged in overnight resulted in *less* charge than what I started with if I didn't turn the screen off. I called T-mobile, talked to Samsung tech support twice... and all they could offer was to have me send the Tab back for replacement.
I was at a loss. I nearly did a hard reset in frustration, thinking I had screwed something up royally.
Then I saw the resistors in the pictures in this post:
http://forum.xda-developers.com/showthread.php?t=845844&page=3
and something clicked. I had been assuming that the *cables* were the difference between the iPhone and Tab chargers... but there isn't enough room for resistors in the cables! (Well technically, there is, but regardless...) The resistors must live somewhere else... and, I reasoned, that somewhere must be inside the USB->outlet adapter. So I pulled out the 'proper' Samsung adapter, plugged in the Tab, and voilà... a perfect fast charge.
So this is why the Tab won't charge with an iPod (or Sony-Ericsson, as it turns out) mains USB adapter OR USB-port car charger: the circuitry to let the device know it's capable of a full 2A delivery doesn't live in the Samsung cables; it's only present in the adapter. If that's not there, the device thinks it's connected via USB (and will, in fact, say "USB Connected" every time the charger is plugged in) and won't charge more than a trickle.
So that's my story, and hopefully it can save someone else some pain and frustration. Thanks for giving me the floor.
Click to expand...
Click to collapse
I've recently seen (somewhere) a usb pigtail cable that shorts the pins to make the tab (or any other usb chargable phone) think it's hooked up to a wall charger, rather than a trickle charging usb port.... I need to find that again and just order a few to have in my various cable bags.
If you do find it again, please post it here. Definitely something I'd like in my bag of tricks as well.
Just as an FYI, the 2A charger that came with my Nook Color charges the Tab just fine from mains, even indicates charging. Makes sense, since both devices have a 4000mAH battery.
It's also a nicer unit for travel, it's nicely rounded, the prongs fold into the body of the charger, and you can pick it up from Barnes and Nobles stores just about anywhere in the US. Still doesn't solve the Tab cable issue though.
Croak said:
Still doesn't solve the Tab cable issue though.
Click to expand...
Click to collapse
I'm planning on hacking apart a spare Tab cable so that it goes to a female microUSB; no more multiple cable types then. The stock Tab cable doesn't appear to have more than 6 pins, of which I'm sure a few are grounds.
Someone recently posted a link to the first cheap 3rd-party cables:
http://www.dealextreme.com/details.dx/sku.51931
Get those with a 6' USB extension cable and the Nook charger, and that may be a winning combination. I ordered four the the charging cables yesterday, and I'll try to remember to post whether or not they work out well.
Resonance, what are you planning on using for a car charger, if any? I really like the Navigator app, but it's just not practical if I can't keep the Tab charged while using it.
Does anyone know if there are any USB->12v adapters that have the right circuitry for the Samsung? For that matter, do any other devices use the same amperage detection setup the Tab does? It would be good to know what components are cross-compatible.
Thanks for the info.
How about a list of chargers that work fine on the GTab.
1. Garminfone charger (1amp - works great and I use it as my primary charger)
mattcelt said:
Resonance, what are you planning on using for a car charger, if any? I really like the Navigator app, but it's just not practical if I can't keep the Tab charged while using it.
Click to expand...
Click to collapse
A 12V inverter, attached to the standard wall charger. :/
I bought the Duragadget 12V->USB charger, since it was advertised specifically as a 2A charger for the Galaxy Tab, but it DOES NOT work as advertised (the Tab treats it like a any other low-current USB port, and even offers to mount mass storage, heh).
Using the inverter and the wall charger worked just fine, though it was a bit clunky and unstable (on mine, the prongs aren't tightly gripped, so it bends out of place easily).
Does anyone know if there are any USB->12v adapters that have the right circuitry for the Samsung? For that matter, do any other devices use the same amperage detection setup the Tab does? It would be good to know what components are cross-compatible.
Click to expand...
Click to collapse
I'd been contemplating giving the Duragadget charger with integrated cable a try, but having been burned once by Duragadget, I'm a bit hesitant to do so.
ResonanceZero said:
Someone recently posted a link to the first cheap 3rd-party cables:
http://www.dealextreme.com/details.dx/sku.51931
Get those with a 6' USB extension cable and the Nook charger, and that may be a winning combination. I ordered four the the charging cables yesterday, and I'll try to remember to post whether or not they work out well.
Click to expand...
Click to collapse
OMG...I bought a charger cable from amazon SOLD BY AMAZON marketed as OEM samsung charger and I got the same one in the deal extreme page. WTF...paid $12 for it too.
ResonanceZero said:
A 12V inverter, attached to the standard wall charger. :/
I bought the Duragadget 12V->USB charger, since it was advertised specifically as a 2A charger for the Galaxy Tab, but it DOES NOT work as advertised (the Tab treats it like a any other low-current USB port, and even offers to mount mass storage, heh).
Using the inverter and the wall charger worked just fine, though it was a bit clunky and unstable (on mine, the prongs aren't tightly gripped, so it bends out of place easily).
I'd been contemplating giving the Duragadget charger with integrated cable a try, but having been burned once by Duragadget, I'm a bit hesitant to do so.
Click to expand...
Click to collapse
looks like that car charger is the same as the one you bought with a USB cable included.
nacron said:
looks like that car charger is the same as the one you bought with a USB cable included.
Click to expand...
Click to collapse
Good eyes. I thought it was a different unit with an integrated cable.
Has anyone found a functioning 12v charger?
yes, the verizon store has a 12v charger for the galaxy tab, but that was the only place I was able to find one... other than online.
Hi,
Can anyone else confirm that the Nook charger works for the Tab?
I've tried other high current (2.0+ amp) chargers. Some designed for the ipad and some not, and I always get the trickle charge icon and it's treated as a computer USB connection (Mass storage device options, etc).
How much was the Verizon charger?
Thanks!
stock wall charger works for me.
knowthenazz said:
Hi,
Can anyone else confirm that the Nook charger works for the Tab?
I've tried other high current (2.0+ amp) chargers. Some designed for the ipad and some not, and I always get the trickle charge icon and it's treated as a computer USB connection (Mass storage device options, etc).
How much was the Verizon charger?
Thanks!
Click to expand...
Click to collapse
Google the gobatt 2 charger. It comes with a usb adapter that charges the tab on any charger.
texasreb said:
Google the gobatt 2 charger. It comes with a usb adapter that charges the tab on any charger.
Click to expand...
Click to collapse
Hi,
Thanks for the tip. I can't find much information about the Scosche GoBatt 2 charger, or the adapter that comes with it. Today I tried other Scosche chargers, including their iPad charger, and it didn't seem to work.
Can you give some more details on the adapter that comes with the GoBatt 2?
Thanks!
Got this travel adapter by ZipKord with 2 - 1 amp outlets. Works with the OEM cord and also the Gomadic tip made for the Galaxy Tab. Just need to be careful it's not the older version that only has the lower power outlets. Cheapest I could find was $13+, so if it's less, it's the lower power. With the Gomadic tip and reractable cord, it says it's charging.
EVO 4G 9292 - Travel Adapter By ZipKord
Also this Scosche battery pack seems like it would work. Has 2 - 1 amp USB ports. I ordered one and should get it tomorrow.
Scosche IPDBAT2 Portable Back Up Battery for iPad and iPod
Oops - can't do links. Just search in Amazon. It's where I got both.
Gomadic cord and tips from Gomadic. Love losing the excess clutter (cords).
galaxy tab 7 charging while turned on
can someone explain well how to build the adaptor for charge galaxy tab 7 while it turned on?
is it possible to have a scheme with picture and some photos which describe the work to do?
thanks. and excuse me for bad english.
mattcelt said:
Hey guys - I've been dealing with a Tab charging issue for a few days, and finally solved it... but I thought I'd post the problem and solution here in case it can save someone else a load of frustration if they run into the same problem.
From what I've read, we know that the Tab only draws .5A power from a USB socket, but that it draws ~2A from the wall, and that it knows the difference by testing for a short on the TX/RX USB data wires. (Correct me if I'm wrong on the details, but that's the general impression I've gotten.) We also know that the iPhone/iPad/iPod uses a pair of resistors instead (per the USB spec) to determine the current-delivery capability of the source. (I'm no EE, so I'm a little fuzzy on how that works from a technical perspective.)
So to set the stage: I had brought the USB cable for my Tab with me, but had neglected to grab the USB->outlet adapter for the mains. Similarly, a friend who was on vacation with us had forgotten the charging cable for his iPhone. Thinking I was killing two birds with one stone, I bought an aftermarket USB charging cable for the iPhone which had a separate USB->outlet adapter. His iPhone charged swimmingly, and when I charged my Tab overnight (screen off, starting at ~89% charge) using my cable and the aftermarket adapter, it worked flawlessly. No problem, great solution, or so it seemed...
...until I got home. Suddenly, my Tab wouldn't do more than a trickle charge - the same charge it gets when connected to the USB port on my laptop. (I could tell this was the case because of the small red 'x' next to the charging symbol in the battery icon - which I hadn't noticed while on vacation.) A 2.5-hour car trip using Navigator (screen on the whole time), even with the car charger connected, killed the battery completely. No matter what I did - shutting down apps, rebooting the device, resetting every option I could find - I could not get a fast charge to happen. Even leaving the device plugged in overnight resulted in *less* charge than what I started with if I didn't turn the screen off. I called T-mobile, talked to Samsung tech support twice... and all they could offer was to have me send the Tab back for replacement.
I was at a loss. I nearly did a hard reset in frustration, thinking I had screwed something up royally.
Then I saw the resistors in the pictures in this post:
http://forum.xda-developers.com/showthread.php?t=845844&page=3
and something clicked. I had been assuming that the *cables* were the difference between the iPhone and Tab chargers... but there isn't enough room for resistors in the cables! (Well technically, there is, but regardless...) The resistors must live somewhere else... and, I reasoned, that somewhere must be inside the USB->outlet adapter. So I pulled out the 'proper' Samsung adapter, plugged in the Tab, and voilà... a perfect fast charge.
So this is why the Tab won't charge with an iPod (or Sony-Ericsson, as it turns out) mains USB adapter OR USB-port car charger: the circuitry to let the device know it's capable of a full 2A delivery doesn't live in the Samsung cables; it's only present in the adapter. If that's not there, the device thinks it's connected via USB (and will, in fact, say "USB Connected" every time the charger is plugged in) and won't charge more than a trickle.
So that's my story, and hopefully it can save someone else some pain and frustration. Thanks for giving me the floor.
Click to expand...
Click to collapse
potential solution
found this on youtube, looks like it has great potential:
forum won't let me post url links, but this is the video code in you tube. We're all geeks here (I think) so you know where this goes :
=uPc-ZA3t5aY
hope it helps!
Related
My battery discharged while I was travelling - it went to <10% and shut off by itself. I left the original HTC microusb over seas and so I used my old Motorola microusb to try to charge the phone. After leaving it overnight a number of times I thought the battery was dead. I ordered a new battery (from Mugen) and tried to charge that.
All I get is a flashing orange/red light. The phone does not turn on.
I have tried charging on both the AC charger and via PC usb port.
Are all MicroUSB cables universal? I can't get a straight answer about this from HTC's customer support. Every time I call someone gives me a different answer which leads me to believe that they have no clue what they are talking about.
Is there anything I can do to remedy this?
The HTC AC charger is rated at 5V 1A, while my old Moto charger is rated at 5.1V 850mA. Could I get a charge by using slightly higher voltage with lower amperes?
I really would like to avoid sending it back to manufacturer warranty so if there is any other alternate route I can take please let me know.
I have some cheap MicroUSB cables and they seem to charge very slowly compared to the HTC one. There may be a difference, but I suspect the cheap cables are just plain cheap.
No the Motorola charger wont have done it any harm, 0.1volt wont make a difference, and charging at a lower current is less likely to cause damage.
Could I have damaged the phone by using a different companies' cable?
Is there a chance that the phone is FUBAR? Should I be able to turn it on if its plugged into a power source even if the battery is dead?
please excuse the bump
need to know
*bump*
I've actually tried all the different combinations of charging and they all seem to work fine
I've tried a cheap microUSB cable with the official charger, official microUSB cable with iPhone charger, cheap microUSB cable with PC, another cheap microUSB cable in my friend's car, and even a Nokia microUSB cable in all the mentioned combinations
They all just gave different current readings (from CurrentWidget) but in the end they all worked well. I'm not sure if a Motorola microUSB would have modifications that cause incompatibilities though
I also tried different Micro-USB Cables and my DHD still works normally.
me too have the same problem. I got a total of 3 diff USB cable. One give me 330mA, one give me 120mA and one gave me only 50mA. i do not mind spending the money if i know how to choose a USB cable which can give me 330mA everytime i charge. Anyone knows how to spot the correct ones?
Neurosis said:
me too have the same problem. I got a total of 3 diff USB cable. One give me 330mA, one give me 120mA and one gave me only 50mA. i do not mind spending the money if i know how to choose a USB cable which can give me 330mA everytime i charge. Anyone knows how to spot the correct ones?
Click to expand...
Click to collapse
Any Blackberry USB cable should work..
used Motorola cable many times. No issues.
Might be a fluke that u busted ur phones charging system.
The USB cables are all the same and have no effect on charging current. The charging current is determined by how the two data lines within the cable are terminated in the charging device. If the data lines are left open ciruit, the phone interprets this as being a USB charger and will therefore only draw a maximum of 500mA to prevent damage to a PC's USB port. Chargers that are capable of delivering more current (such as a wall charger) connect the two data lines together. The phone then interprets this as being a charging device which is capable of delivering a higher current and will draw greater than 500mA. If you look at "Menu - Settings - About phone - Battery" it will state either "Charging (USB)" or "Charging (AC)" depending on what you are charging from.
I just received my stash of charging gear for my Optimus 7 today, bought from DX. Having read everywhere that USB chargers are 5V +/- 10%, and seeing that the original LG charger outputs 4.8V, I thought my purchase was ok and that this charger would work.
Turns out it doesn't. When I connect the phone to the charger via USB, I lose control of the touchscreen and the system gains a mind of its own. I literally just hold my phone in my hand and stare while it randomly enters hubs and either opens an email message or dials someone. The physical buttons still respond correctly, and it's not until I disconnect the charger from the wall socket or the phone from the USB cable that I can regain control of the phone. My guess is it's a hardware fault and not software.
Granted this unofficial charger cost me around $1, but I got some similar 5V car chargers to go with it, and I've never had problems with other USB chargers.
Unofficial charger specs:
Input: 100-240V 0.15A (0.15A) 50-60hz
Output: 5V 1A
Does someone else have this issue? Is the Optimus 7 an uncommon device for requiring 4.8V input instead of 5V?
Your problem is NOT the charger, as that has nothing to do with the functions of the phone.
Your problem is that your LG Optimus 7 E900 is a DEMO unit, with a DEMO ROM. And until you flash a stock ROM onto your phone, you will experience the demo played out while connected to a power source.
You sure? Because I tried it with the 5V 1A car adapters and no problem, and the original 4.8V 1A charger gives me no problems either.
How do I check my ROM version? Firmware is 1.0.7.10, OS is 7.0.7008.0 after the February update.
Can you get us video on this?
Please excuse the ****ty video quality
That is most fascinating. I recommend you stop using that charger on your phone
So, obviously, you do NOT have the demo ROM as I suspected initially.
Since you say it works with another 5V 1A charger, then I think this specific charger may be sending unexpected, random data signals down the USB cable, resulting in the unresponsive and bizarre behaviour. Since the original charger works well, and charges pretty fast, just stick with that for now.
At least you got the update, here in Canada, we are still waiting for our first update.
And your English is so good, and without any accents...Are you sure you aren't from our here (North America)?
This is true magic Really I have no eplanation on this problem. It is only 0,2V
Yeah, and there I was thinking that the whole point of USB charging is that it's universal and totally compatible, no matter what adapter you buy and what cable you use, provided it connects well.
It seems this is not the case, and I'm weary of trying another third party USB charger, as I still cannot tell if this phenomenon is unique to the Optimus 7 or not. Sadly, the only other MicroUSB phones I have lying around don't actually support charging via this port, just data transfer.
i also admit that im "dazzled" by ur -smart-phone...
probably that adapter is"magical" somehow... did u try it on another phone??
+i also use different chargers but never had any abnormalities so far..
Though i use the original chargers that came with my blackberry 9700 and htc-desire, and just checked the blackberry output is 5v!! i cant read the htc...
So, probably that adapter of yours is a "mutant from another place"...
confirm, htc is also 5v...
ps2- i'm also on 7008, and havent got any issues with charging on both 7004 and 7008
The problem is in the charger, it's too chinese . I had this issue with other touchscreen phones, like SE X8, X10... Just change the charger, obviously it has some hum/noise...
lol...
too chinese? lol
im having the same issue when i use the lg power adapter.. it doesnt always happen but when it happen the touch screen just when berserk.
i always thought that it happens on all units. uh oh
To be honest, I thought you were crazy till I bought a Chinese adapter as well. Don't know the voltage, but I'll check it tomorrow. I think it might have to do with the way the unit is shielded, or not. The only time I wiggs out is when I leave it on the desk, but as soon as I pick it up and pull it a few inches away form the desk or any other object it works fine. But as soon as I put it back down, the screen does the same thing.
I have a usb plug that I plug into the computer that didn't do that at the same desk, I'm going to bring in my other charger and see if it rule out the outlet / interference or just the cheap a$$ adapter....
The only part that worries me, and the only reason I might stop using it, is it takes a bit from the time I unplug it to the time the phone realizes it's unplugged and the charging icon stops. Which doesn't happen with any other charger.
I had this problem too.. until I realized it affected my other touch screen devices too (Galaxy S, Galaxy Tab)... Turns out the 5V charger was the problem. Replaced it with a 5V charger of Philips/Belkin/Samsung/LG and all worked..
The unbranded 5V chargers don't work well with capacitive screens as they seem to be letting off some extra current.
Hi all, just came 3 days ago from an htc hd2, and so far I am more than happy with it.
I have only one complaint and maybe you guys will help me sharing your experience : I can't charge this phone in my car while using gps.
It seems that the power adapter is not powerful enough to charge the phone screen on.
The car charger has a 5v 1000ma output, more than the regular wall charger provided by Samsung and it was working well before with my HD2 so I have no clue about this problem.
Did you experience that issue too, else can you share what car charger do you use?
try to buy new standard car charger with micro plug.. 13 eur and you will be saved..
Sent from my GT-I9100 using XDA App
Charger doesn't matter unless the phone is dropping into USB charging mode - phone limits to around 600-650 mA by default.
Custom kernels can bump this limit up for I9100 users. I777 users are screwed - we've got a crippled charger chip.
I had the same problem, I used the samsung one, useless, so I used my iPad charger, which is 2A, and charges the iPad quick, still useless. We drove from Bathurst NSW, down to Melbourne, about 10 hour drive, plugged in all the way using GPS, and about an hour from home, the connect to charger warning came on!! So once I stopped GPS, it started taking charge. Looks like when the phone is in use, it draws more then it takes charge, plus I read somewhere on here the phone is limited on the charge it takes, so using the 2A does nothing different then the stock 500mA charger.
I always had this problem with my Nexus One, although they are different phones, the problem is the same, uses more power then it can recharge in USB mode.
After trying 3 or 4 different charges I remember that I found one ultra-cheap 'made in taiwan' from a street seller that worked very well.... so it's kind of a lucky shot!
good luck!
Im using a genuine Samsung SGS2 charger and I can charge and run Sygic just fine. I started my journey with 80% and 40mins later I was up to 91% when I stopped and got out. (not in aeroplane mode..)
Very interesting feedbacks... So that confirm that is clearly not a matter of output amperage power.
It is now the same problem on the galaxy tab 10.1, for quickly charge this tab you need the Samsung compatible usb adapter.
It can be likely with a tab bringing a proprietary plug, but I didn't thought it will be the same with a Samsung phone bringing a regular micro usb plug. Quite frustrating and disappointing!
I will search around a micro plug car charger as suggested by redzion, but actually I don't clearly see the difference with my usb charger + a micro usb cable.
Double post, sorry.
If I use the usb cable from my cd player I have the same problem but if I use the official Samsung car charger Ithe only problem I have is the phone getting stupid hot
Sent from my GT-I9100 using xda premium
Oh Samsung, when you will understand?!
Samsung DOES follow the USB charging standard - it goes to its highest current setting when a charger that follows the standard is connected.
Note that iPad/iPhone chargers do NOT follow the standard - Samsungs will treat these as USB hosts and limit to 450 mA instead of 600-650.
Modified kernels can increase both of these values on I9100s.
The only thing Samsung really did **** up is counting screen/CPU current usage against the charge current limits - that's just stupid.
So the charger has smarts. On the i9000 factory chargers, the data pins were bridged. Bridging these pins manually on a USB cable when connecting to a USB source (such as a PC) enabled full current charging. You can see this in Settings -> About; it will say either USB or AC charging.
Do you think this is the case with the i9100?
I don't condone testing this theory on your i9100. Increasing the max current via custom ROM may be a safer solution.
I had the same problem. Two things fixed it for me:
1) I bought this charger: Sony Ericsson AN300 Micro USB 10€
2) I am using a custom kernel now
Any charger that is rated at 1000mA or more (per port) will do just fine. The problem is the cable - you need a quality microUSB cable, or it won't provide all the juice you need. I had the same issue, and I swapped three chargers until I found the real culprit.
Try with the charger you have now and the mUSB cable that was in the phone box - it should work well with that one.
I just press the power button to turn the screen off. when i need the sat nav i press the power and it still tracks you so there is no delay. With the screen off it does charge.
same problem
Duffman19 said:
I just press the power button to turn the screen off. when i need the sat nav i press the power and it still tracks you so there is no delay. With the screen off it does charge.
Click to expand...
Click to collapse
You are right, but even if it is better than nothing the charging time is still a big problem.
Yesterday I drove for at least 40mn phone off. Arrived to destination, I turn the device on: it charged only from 0 to 5%
I would like to test the mariusi theory concerning the Samsung micro usb cable, unfortunately on my SgsII box I just have a wall charger, no a microusb-usb cable.
Entropy512 said:
Samsung DOES follow the USB charging standard - it goes to its highest current setting when a charger that follows the standard is connected.
Click to expand...
Click to collapse
Is there a way to know before buying if the charger respect this charging standard?
I have some cheap usb chargers here and no one is a fast as the one provided by Samsung.
Entropy512 said:
The only thing Samsung really did **** up is counting screen/CPU current usage against the charge current limits - that's just stupid.
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Maybe for safety purpose? Gps phones can become very hot behind the car glass.
Samsung are trying to "encourage" you to buy only their official accessories. To do this they've wired something differently in their chargers and cables. This "problem" exists on the Galaxy Tab too and can be solved with this adapter...
http://www.ebay.co.uk/itm/USB-car-w...ccessories&hash=item2c5c07736b#ht_3084wt_1163
It's cheap and turns a trickle charge into a full charge. I don't know the specifics of what they've done, but their USB charging just isn't the same as most others manufacturers.
Archer said:
It's cheap and turns a trickle charge into a full charge. I don't know the specifics of what they've done, but their USB charging just isn't the same as most others manufacturers.
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Great find.
Pretty sure it just bridges the data pins.
Hello.
I m having a problem with my transformer. Right now it is charging slow as if it was connected to the computer and not the wall plug. Also the message "Connect your Charger" won't go out of the screen, even if it is connected or fully charged. I flashed a custom ROM to see if it fixed something, but I had no luck. The cable works fine to connect the transformer o my PC the only thing wrong is that is is not charging properly and the message won't go off. Do you have any idea of what could be happening? My wall charger is model OB-1LF, which I believe is not the one with the known fault. Any ideas?
the adapter is surely broken.
This will sound nuts but, put your wall charger in a plastic baggie [push out all the air and then seal the bag] and put it in your freezer compartment for say 3hrs. Take it out [still in the bag] and let the charger warm up to room temp.
The charger may now work. It is worth a try. You would be trying to be sure the thermal fuse inside the charger is reset. I brought one back to life that way.
hshoem1
the TF uses pin 7 in the USB connector to signal the charger to use the 15v output. If the charger does not see a gnd on pin7 it will only charge at 5V as ypou are seeing. Are you using an extension usb cable? If no then check the pins on the TF and cable for bent or damaged pins. Also try the freezer as the charger may have gone into safety reset.
Thanks for the answers. I will try the bag and freezer to see if it gets fixed.
I know that this freezer trick works (also with broken hard drives too apparently), but what's the physical reasoning behind it? I swear I've seen a good explanation of it before but I can't remember..
Same problem here... Even had the charger replaced but of no use. It does charge wth a different (do it yourself) charger usig the same cable.Maybe that doesn't have the 5v/12v mode or something...
Going to order a new adapter and hope thatll fix it otherwise I'll send the entire transformer for repair i guess :/
I just got one today (got a good price on Amazon)
it just will not charge, tried all the fixes! not too happy as i went for the asus over the ipad and apparently quite a few people have charging issues with it.
charges very slowly through my laptop
From reading posts on forums is sounds like a few people are having it and Asus should of recalled the charger.
phone call to Asus tomorrow
asdfuogh said:
I know that this freezer trick works (also with broken hard drives too apparently), but what's the physical reasoning behind it? I swear I've seen a good explanation of it before but I can't remember..
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There is overtemp protection circuit that should reset once the charger cools, but apparently it needs to cool down past room temp. The freezer is cold enough to reset it. I would not buy a new TF charger search for devcakes discussion there several aftermarket chargers that work well
Check the cable. I had the same problem. At first I thought it was because of faulty charger and had it returned and got a new one from Asus, but still had the same issue. Then I returned the cable for a new one, it worked flawlessly.
A plus: Asus gave me new cable which was much longer than the original one.
the cable is fine, used it to charge via my laptop
I had the same issue with my charger. I called up Asus and was able to send it in for repair, after a couple days they mailed me a new charger and cable.
Sent from my Transformer TF101 using xda premium
mglancy23 said:
the cable is fine, used it to charge via my laptop
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Charging with your laptop does not involve pin 7 and supplies 5V. If pin 7 or that conductor is bad or you use an incorrect USB extension cable, the pin 7 signal will not get to the charger and will not supply the 15V charge voltage for normal charge.
Rumbleweed said:
Charging with your laptop does not involve pin 7 and supplies 5V. If pin 7 opr that conductor is bad or you use an incorrect USB extension cable, the pin 7 signal will not get to the charger and will not supply the 15V charge voltage for normal charge.
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Cheers will send the cable as well to be sure but am pretty confident its the power adapter.
Hopefully i will have an adapter for next week.
I had a brief play on it and i was quite impressed, the stock browser was surprinsignly good and may unistall dolphin.
I tried the freezer trick, but it didn't worked. I ordered another wall charger to see if it works. What's really weird about this is that the Connect your Charger message will not go off the screen. It doesn't matter if it has 100% charge it will still show "Connect your Charger".
In my case my Transformer didn't want to charge at all. The red light never came up while connected, the only way to fix it was to drain my Transformer all the way until shutdown and then plug it in and voila! It started charging again ever dince.
Great tips by the way!
Thanks
Sent from my Atrix 4G using Tapatalk
Just an update, after ordering a new adapter (with cable) it now works... Appearantly the cable was the problem afterall...
New cable with old charger = ok, new cable with new charger = ok, old cable with new charger = no go, old cable with old charger = no go.
And old cable with 3rd party adapter supplying 12V = ok, heh...
New cable is longer indeed, now I just need to think if I wanna go through the RMA process again for the old cable. But yeah, cable was the issue (out of nowhere btw).
dagrim1 said:
Just an update, after ordering a new adapter (with cable) it now works... Appearantly the cable was the problem afterall...
New cable with old charger = ok, new cable with new charger = ok, old cable with new charger = no go, old cable with old charger = no go.
And old cable with 3rd party adapter supplying 12V = ok, heh...
New cable is longer indeed, now I just need to think if I wanna go through the RMA process again for the old cable. But yeah, cable was the issue (out of nowhere btw).
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The Pin 7 Connection I referenced earlier is bad. This prevents the charger from outputting 15V.
Rumbleweed said:
The Pin 7 Connection I referenced earlier is bad. This prevents the charger from outputting 15V.
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Yeah, I read your posts about that... couldn't see anything wrong with it on the outside though (with my eye) so unfortunately no clearly bent usb-pins or anything.
Any tips on things I can check? Could easily be on the inside as well of course in which case I can just forget about fixing it. At least it still works with another (non asus) adapter.
Mine was also doing a slow trickle charge. I ended up getting a new charger, but found that the problem was with the cable, not the "wall wart". I can still use my old one with the new cable and works fine as well.
Hey all, quick question.
I have my Nexus 7 installed in my car. Originally it was getting power from a 500mah USB car charger, but it didn't provide enough power to the tablet when running GPS/maps, etc.
So I bought an "8Ware Dual USB Car Charger 5V/2A" to try. I plugged it in, and the tablet doesn't detect it or charge from it. However I can plug my Galaxy S3 into it and it charges fine.
Really confused about this - it makes no sense.
Any ideas?
Thanks in advance!
I understand your frustration and it sucks!!
But sometimes even when it says UNPLUGGED and NOT CHARGING, just leave it there for 30-60 minutes. You might see that your battery actually increase... This happens with my Griffin PowerJolt Dual USB car charger also.
You can either blame the device or you can start blaming other issues like the charger, the usb cable etc but for me, I blame primarily on the device.
- Charles
chaddeus said:
I understand your frustration and it sucks!!
But sometimes even when it says UNPLUGGED and NOT CHARGING, just leave it there for 30-60 minutes. You might see that your battery actually increase... This happens with my Griffin PowerJolt Dual USB car charger also.
You can either blame the device or you can start blaming other issues like the charger, the usb cable etc but for me, I blame primarily on the device.
- Charles
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Thanks for that. I tried plugging it in for a while but it definitely didn't get a charge.
Hey All.. I looked forever to find a solution. The Targus 2A car charger has a small (3") adapter cable that comes with it purportedly for Galaxy Tab. That little cable with the data wires shorted on the device end allows the N7 to be charged from ANY 2A car charger. I'm using the adapter with a Scosche dual 2.1 Amp Car Charger
Adapter picture
Targus Charger
Edit: I just built a usb cable with the data wires shorted on the Nexus end (cut, strip, short micro usb end green and white, remake connections red to red and black to black, insulate splices individually, wrap all in electrical tape or heat shrink for strength and beauty) and it works with all chargers. Took about 20 minutes.