Database Info

Fast charging N1

It seems the only way to fast charge a N1 is with the supplied wall charger. Standard Micro USB chargers whould only allow at much as 450mA of charge current regardless of the adapter current capacity.
The bundled charger however, manages to push 900mA into the N1. I made a cut in the charger wires and measured the current draw to make sure.
Now.. I'd like my car charger to be able to do the same. There must be some hack in the plug of the N1 charger since there are only 2 conductors from the case to the plug. You can see that the plug is somewhat longer than similar Micro USB plugs..
So I tried to see if one of the 3 unused pins can tell me anything but.. they seem unconnected as far as I could tell. Diode measurement (to test for any digital part inside) also did not produce any results. The next obvious step is to take the molded plug apart but I'd rather not...
Does anyone have any clue as to what makes that plug so special?
And please - I did my tests with a bench power supply - not the car chargers - so don't go around telling me it has to do with charger current capacity.
Thanks,
Nir

are you sure the micro usb cords you are using are able to handle the amps? most chargers made prior to now, only push about 450mA, the G1, and N1 chargers i have push a full amp though. I just ordered a car charger that pushes an amp too. There is nothing "special" about the plug.

followinginsanity said:
are you sure the micro usb cords you are using are able to handle the amps? most chargers made prior to now, only push about 450mA, the G1, and N1 chargers i have push a full amp though. I just ordered a car charger that pushes an amp too. There is nothing "special" about the plug.
Click to expand...
Click to collapse
I beg to differ. All the cords can easily supply 1 AMP. It is the phone itself that decides how much to draw from the charger based on something IN THE PLUG.
I am an electronics engineer so do understand I know perfectly what I am talking about
And your 1A car charger does not supply anything over 0.45A to the phone.. you will see that if you are using the phone while it charges (say nav or phone call) the phone actually looses some charge albeit it being charged... This will not happen with the stock wall charger.

I have a 900mAh car charger that I use and it does in fact give 900mAh to the phone while charging. I can tell because I used a 450mAh charger at home before and it was slooow and I could drain my phone while charging it. With the car charger I can stream music with spotify, use the GPS, have the screen on full brightness and the battery % will still go up.
I also bought a new wall charger recently, which is 850mAh on the USB port and has a 350mAh charger for a loose battery as well, works quite nice.

Has anyone measured the voltage or put a scope on the output of the stock charger?
maybe stock charger has a slight variance in voltage over USB chargers or some signalling going on and this tells the N1 to take more current from it?
I would like a solution to this too I've seen my phone discharge while on a supposedly 1A car charger using co-pilot.

SBS_ said:
I have a 900mAh car charger that I use and it does in fact give 900mAh to the phone while charging. I can tell because I used a 450mAh charger at home before and it was slooow and I could drain my phone while charging it. With the car charger I can stream music with spotify, use the GPS, have the screen on full brightness and the battery % will still go up.
I also bought a new wall charger recently, which is 850mAh on the USB port and has a 350mAh charger for a loose battery as well, works quite nice.
Click to expand...
Click to collapse
Forget the numbers on the chargers - what counts is what really goes into the phone and that needs to be measured with a current meter (test equipment). What you may think to be fast might not be that.
Original HTC chargers obviously do the trick of fast charging but this comes at a price compared to the $3-$4 garden variety on Ebay and the likes.

now I cannot help you with the electronics at all, but, my old HTC Touch Pro charger seems to charge the same as the one which came with the phone, is this correct?
(suits me if it is, as then I have a charger for home and work)
my blackberry bold 2 charger only says it outputs 700MAh, but both the google and htc chargers both say 1.0A

dnts said:
Forget the numbers on the chargers - what counts is what really goes into the phone and that needs to be measured with a current meter (test equipment). What you may think to be fast might not be that.
Original HTC chargers obviously do the trick of fast charging but this comes at a price compared to the $3-$4 garden variety on Ebay and the likes.
Click to expand...
Click to collapse
Yes, it is just anecdotal evidence as I don't have any equipment to measure it. But my phone no longer discharges when I use it while charging, which it used to do with the old charger I used. So while I can say for a fact that the charger I use now is faster, I can't say by how much (this goes for both the car charger and the one I put in the wall socket).

I ordered this charger a few weeks ago and it charges my phone as fast as the original charger. The label says 5v / 1200mA.
Genuine Nokia Mini AC-10U US Type AC Charger (100~240V)
$7,25 and free shipping. (Takes a while before you get it tho.)
GazzaK said:
now I cannot help you with the electronics at all, but, my old HTC Touch Pro charger seems to charge the same as the one which came with the phone, is this correct?
Click to expand...
Click to collapse
HTC Touch Pro = mini USB
Nexus One = micro USB

Not an engineering here, but I am guessing the phone not always drawing more than 500ma may be is to do with the charger itself.
There is this "fast charge" USB standard where a wall plug has the USB data pins shorted to indicate that it is a wall plug and hence the phone knows when to draw more power. So even if the charger is rated 1A, the phone might not know if it could utilize that if those pins aren't shorted. Try doing a quick Google on this ....
If someone can test if the stock charger that came with the phone in fact does have those pins shorted that would confirm part of this theory.

For all practical purpose - I used two cables/plugs with a bench adjustable power supply. Simple micro USB plug would only let me draw 450mA regardless of power supply voltage in the range 4.5-5.5V. Tried shorting data pins - nothing. Tried shorting spare pin to VCC or GND or any of the other pins - nothing.
Used original cable and plug - draws 900mA at voltages from 4.9-5.5.
So it's in the plug somehow.
Tried (very difficult) to see if the pins on the plug are shorted and all 3 spares (except for 5V and GND) seems unconnected.
Next step is the irreversible hot knife...

I'm bugged by this, too. I tested with my desktop dock connected to my car charger (which states 1000 mA): it loads slowly and my battery widget reports USB- instead of AC-charger.
Might it be that the phone tries to load more than 1000 mA at the beginning to be sure that it doesn't overload the charger? And if that fails, it falls back to 500 mA?

Could N1 use a simple logic of:
- always watch the voltage
- start drawing 500ma (or whichever is the lowest current as per USB spec)
- increment in say 50ma steps
- if voltage drops below 4.x V, back off and stay at that level

I just did a little test of my own. I have a Palm Pre car charger (actual Palm brand one labeled as 1000ma output) and I plunged my N1 into it on my way home from work. In twenty eight minutes, my battery went from 47% to 70%. Much faster than plugging into my computer, which is 500ma max. I don't have any fancy test equipment, and don't claim to know a whole lot about electronics, but seems pretty fast to me.

I have a 4-port 2A 5v USB charger, and connecting it to my Nexus OR Milestone with a MicroUSB cable (the one that shipped with either phone, or the one from my Kindle) yields painfully slow charging - it basically won't charge if you are using the phone.
Connecting the Nexus One charger yields fast charging on either phone - so it is not HTC (or Motorola) proprietary.
The Milestone comes with a 900mA USB plug, and connecting THAT to either phone with either of the MicroUSB cables yields fast charging.
I have another aftermarket 2 port 2A 5V USB wall charger (brand: T'nB) AND I have an iPhone USB plug, and both give fast charging on the Milestone, and I have not yet tried them on the Nexus One.
Breakdown (on things I've tried):
FAST CHARGING on Nexus One AND Milestone:
Nexus charger (either in the US (110v/60hz) or in France (220v/50hz) through an adaptor)
Milestone wall French USB plug (which I think is something odd like 850mA at 5.9v) with ANY microUSB cable (in fact, it seems to charge both of the phones faster than the stock Nexus One plug)
SLOW CHARGING on Nexus One AND Milestone:
USB plug on computer
One aftermarket 4 port 2A 5V USB charger (NOT a hub, only a charger)
FAST CHARGING on Milestone, untested with Nexus One
T'nB 2 port 5v 2A USB wall charger
Apple iPhone 1 port 1A 5v USB wall adaptor

Seems found the answer for Fast Charging N1
I had just do some test for Charging N1 With Original AC Charger , Other band USB Charger and PC USB charger.
1. Orginal Charger give N1 from 0% to 100% at about 2 hour and something.
2. The other band AC charger and PC USB Charger can only finish the same job over 5 to 6 hours.
The Fast Charging is Due to 5.1V (Measured at N1) and 5.2V(Measured inside AC charger). 0.1V Drop is due to resistance of USB cable.
The Slow charged is due to 4.8V (measured at N1) and 5.0V (measured on PC USB and Other AC Charger)
i.e. Original Charger mod from 5.0 V to 5.2V (about 10% increase in Voltage)

Looks my theory is correct then ? N1 watches the voltage and if it droops too much, it backs off the current.
So the key would be: get a charger than can maintain at least 1A @ 5.2V, use
a decent gauge, short wire from the brick to N1.

Has anyone tried a Blackberry charger on the N1? Will they work to full capacity as well? (They're on Amazon for a fiver)

Because the nokia charger is working
http://pinoutsguide.com/CellularPhones-Nokia/micro_usb_connector_pinout.shtml
see info under table.
I tested also HP charger + standard USB cable delivered with Nexus, and it is charching cca 1A.
Then I tested one noname Carcharger + standard USB cable delivered with Nexus, and also charging cca 1A.
I dismantle the noname carcharger and here is a result:
data line (pin2+3) is shorted and connected do + (pin1 ,Vcc) thrue resistor cca 630kOhm.
1 - 4 = 5.1V
2,3 - 4 = 3.2V
rashid11 said:
Looks my theory is correct then ? N1 watches the voltage and if it droops too much, it backs off the current.
So the key would be: get a charger than can maintain at least 1A @ 5.2V, use
a decent gauge, short wire from the brick to N1.
Click to expand...
Click to collapse
I try to use power supply 5.2V 2A with cable without dataline (pin 2and3 not connected) and it is charging 480mA only.

I have now tested with an HTC car charger for the HD2. It's fast charging (tested with Waze running, two bluetooth connections and playing mp3 - and it's still loading the battery, whereas before it would be stuck at the current percentage) and even shows AC power instead of USB.

[Q] got a generic charger....it says-5v 500mah,original is 5v 1a(amper)is this ok?

it says- output :5v 500mah
the original says-output:5v 1a(amper i guess)
will this screw up the battery?

chances are no, considering it is half what htc recommends you charge it with, either it will charge it very slowly (half the current of the original) or the voltage wont provide enough to kick the phone into charging mode and nothing will happen (i.e. the charger "wont work")

Thanks for the help

It'll work, but as panyan said, it'll recharge much more inefficiently than with a 1 amp charger.

Actually... It will charge the phone exactly as charging via USB, as USB is limited to 0.5A.

Yep, it will charge your phone just fine @ USB charging speed, I have a similar charger.

And some of you forgot to mention that the phone will struggle when for example you will play games or use gps. Charge will be insufficient and instead charging it will slowly discharge while using it.
Sent from my Desire HD uing XDA App

Well yes and no, in normal usage it will charge phone, but when you use your phone the way that you would drain the batty in two hours, then it will discharge.

Hey... Yeah if the charger is a car charger then it may not charge fast enough if using GPS software which can drain the battery fast. 1Amp reccomended for faster charging... other than that should charge fine but just slow like USB charging (which has a max of 500mA).
One question guys... I bought a car charger from ebay listed as for HTC phones. It looks like a cheap knock off product with a glowing blue HTC logo when used in the car. The device is rated at 2Amps. Now from what little I know about electronics I've been told that AC/DC Plug packs with more Amps are ok and the device just only uses what it needs. I'm not however familiar whith battery charing when you have a higher rated Amps charger... Would the battery on the phone just be greedy and "ask" for the full 2Amps? Would this then put strain or be dangerous by charging the phone too quickly?
Secondly while we are on the topic of electronics... I'm trying out a super cheap ebay battery supposedly rated at 1600mAH (I know these rating are usually fake). I've noticed the HTC battery is around 4.17V when fully charged. This battery charged up to 4.2V fully charged... Is that dangerous for the device?

2 amp is better, correct me if i am wrong. So the output is 5V and 2A, is that mean the power is 10W every hour ?

2 A charging current (if the phone takes in that much) will damage the battery in a long term use.

It is incredibly unlikely that the phone will discharge the battery faster than it charges unless you're doing something very wrong, e.g. Running a console emulator while downloading a large file over HSDPA with WiFi enabled (but not connected) and using GPS navigation with screen brightness at maximum!
Screen and background services take approx 150mAh, and I doubt radio will take much more than that combined. That puts drain 200mAh less than USB charging, 700mAh less than direct charging.
FYI: There's a spec for USB charging of mobile phones from supported USB ports which can pull up to 1500mA.

DeathJester said:
It is incredibly unlikely that the phone will discharge the battery faster than it charges unless you're doing something very wrong, e.g. Running a console emulator while downloading a large file over HSDPA with WiFi enabled (but not connected) and using GPS navigation with screen brightness at maximum!
Click to expand...
Click to collapse
Hmm... not sure for Desire HD I haven't tested GPS with SatNav software using current widget... I do know that I'm pulling well over 200mA just with basic use at home with Wi-Fi on and GPS & Bluetooth off and I kill all backround apps. I do know that I've been in the car and seen TomTom app on my friend's jailbroken iPhone 3G (or 3Gs) and with the GPS on and not doing anything intensive... we were actually travelling down a long straight highway, the phone was chewing more battery than the car charger could charge, so he switched off GPS.
Ah also guys no need to worry about the 2Amp charger... It sh*t itself on the 3rd car use and no longer works at all. Junk! I also noticed on the 2nd car trip that opening Android SpareParts the charge is displayed as USB Charging not AC Charging so yeah I believe that the car charger was only a standard USB (max 500mA) power output and not 1Amp let alone 2Amps. Annoying how false advertising or labelling is part and parcel with cheap Chinese products.I was meaning to test the charger's output with Current Widget (which is what I'll do for my next car charger) but the charger crapped out and was useless before I got a chance.
One thing I did notice from looking at a log using Current Widget while charging my phone on the A/C charger in standby, the charge tapers off the power output the more the battery is charged. To get an accurate idea of if the car charger is going to be outputting 1Amp I'd be sure the phone battery is down to 40% (or in the 40s) then with all other stuff switched off I'd run a log on Current Widget and turn the screen off for a few minutes. You should have a reading of around +700 to +800mA if the car charger is rated at 1Amp.
Be wary of the cheap Asian knock of car chargers with the coil spring cord and the HTC logo that lights up blue.... Not worth the 3 or 4 bucks they sell on ebay for.
There's a spec for USB charging of mobile phones from supported USB ports which can pull up to 1500mA.
Click to expand...
Click to collapse
There's commonly those double USB cables for laptop hard drives so yeah I can see that if the USB ports are actually giving you the full rated maximum of 500mA you can get 1Amp output with this kind of cable but 1500mA?!? The only way I'd see possible for this is either you have a tripple USB cable connected to 3USB ports that are all outputting the full 500mA (and that's if a triple cable even exists or lets say you solder another one onto a double cable) or you have a USB AC/DC charger or some other USB port/hub you've rigged up which provides more than the USB standards of max 500mA per port. How else is this possible?!? Has the max power output of 500mA changed since USB 2.0 standards?

yeah there are usb 2.0 ports with more than 500mA power supply.
some companys give some extra juice to their (or often only one) usb ports.
for example: i've got an Dell Studio XPS 16 Notebook here. it has 3 usb ports, 2 with normal 500mA supply and one with 1A (for charging your phone, etc).
DN41

Car Charger that works?

Hi.
I'm looking for an advise about car charger that can charge my TF700.
does anyone confirmed that there any car charger that works?
I mean, I saw some posts that says that ASUS' charger is 15v instead of the more common 5v?
but then I saw the charger, it says " Output : 5v === 2A or 15v === 1.2A"
So I assume I can use other car charger that works with other tablets?
can someone confirm this for me?
THANKS

The tablet will only start to detect a charge at 12V.
Charging at anything lower than that will charge about 1-3% every hour.

ShadowLea said:
The tablet will only start to detect a charge at 12V.
Charging at anything lower than that will charge about 1-3% every hour.
Click to expand...
Click to collapse
oh. okay. any recommendation on what charger should i get?
preferably one with dual USB.

USB is not going to work, in any form or capacity. a USB port can only put out 5V at max.
I use a power inverter that puts out 230V (bought it for my laptop a couple of years ago) through a normal outlet. Plugged the charger into that and it charges normally. You could try looking into that.

ShadowLea said:
USB is not going to work, in any form or capacity. a USB port can only put out 5V at max.
I use a power inverter that puts out 230V (bought it for my laptop a couple of years ago) through a normal outlet. Plugged the charger into that and it charges normally. You could try looking into that.
Click to expand...
Click to collapse
well. if that's the case. I might buy another wall charger...

william tanaya said:
Hi.
I'm looking for an advise about car charger that can charge my TF700.
does anyone confirmed that there any car charger that works?
I mean, I saw some posts that says that ASUS' charger is 15v instead of the more common 5v?
but then I saw the charger, it says " Output : 5v === 2A or 15v === 1.2A"
So I assume I can use other car charger that works with other tablets?
can someone confirm this for me?
THANKS
Click to expand...
Click to collapse
YES the ASUS Transformer will only charge from between 12 & 15V. They DO NOT charge from 5V USB.
I have found that the car chargers which have the ASUS 40 pin plug attached to the cable work fine. They have a regulator circuit which outputs 12V at 1.5A minimum.
The ones available on eBay work well and aren't too expensive. They are a little bulky because of the high current circuitry so look at the pictures and make sure that it looks bigger than the average ones and you will do fine.

unfortunately there's no car charger available as of yet.
Sent from my VS920 4G using xda app-developers app

An Carcharger is avilable, i have one and it is working. 15v 1,2A Carcharger with normal Asus connetor. I'm usin it since 2 Month, never had problems. Carcharger is even cooler as the 230V USB charger while charging. Asus Tabel also switch immediately in charging mode. 14€ at Amazon.de.
By the way, why is everyone saying 5V won't work? On my 230V USB charger there's following note "15V 1,2A or 5V 2A"
Well won't need it, just buy this one ( which i have):
www.Amazon.de/gp/product/B007PQ8AN6/ref=oh_details_o04_s00_i01
Just ignore that tf700t isn't written there and that the charger would have 1,5A. Thats wrong, Carcharger has 15V 1,2A.
If you won't believe me, i can make an picture ( that it will have 15V 1,2A and works) otherwise have fun with it

Speedmastersaxai said:
By the way, why is everyone saying 5V won't work? On my 230V USB charger there's following note "15V 1,2A or 5V 2A"
Click to expand...
Click to collapse
Why aren't you reading everything? I said 5V charges too slowly for the tablet to detect, but it does charge. About 1-3% an hour, which is useless when you're using it. It clearly says, in the manual, that it will only charge over USB (5V) when turned OFF and not connected to the dock. RTFM.

SUH said:
unfortunately there's no car charger available as of yet.
Sent from my VS920 4G using xda app-developers app
Click to expand...
Click to collapse
I don't know how many different threads I have to post this in...
http://www.amazon.com/gp/product/B0081BFYY2/ref=wms_ohs_product
Includes a home charger, car charger, and an extra USB cable, that ALL work. I have been using these with my Transformer Prime, and now my Infinity without an issue at all, and they provide the ASUS required specs for charging and work just like the factory provided chargers.

I ran into this issue with my Verizon Samsung Galaxy Nexus. When attached to a charger, if I went into Settings...Battery... it would show the status of the charging process: it would say "USB" when connected to a computer, and charged at a much slower rate, or "AC" when plugged into the supplied charger in a regular outlet, and charged much more quickly.
With most car chargers, it would only show "USB" but there are some car chargers that have the correct wiring so that it was recognized as "AC" and charged as quickly as when plugged into a regular outlet.
I have two of these in my vehicles, and I just checked one of them, the one listed below first, and with the Tablet plugged into it, it shows as charging, as an "AC" source, just as with my Galaxy Nexus.
Here is the one I specifically tested and verified that it works:
Dual USB Car Charger
I do note the 2 negative reviews there, but all I can say is that I've had this one for almost a year, and it has worked perfectly for me with my phone. A brief test with the Asus Tablet confirmed it was seen as an "AC" charger.
This is the other one I have and which works fine with my phone, although I have not specifically tested it with the Tablet (I have no reason to expect it would behave any differently):
HTC T-Mobile myTouch 3G Car Charger
Obviously, I can't be held responsible if somebody else has a different experience with these, or has problems because of it. Just trying to be helpful and report what has worked for me.

You might consider the i-Blason 12V 2A MINI BULLET STYLE CAR CHARGER FOR ASUS Eee TRANSFORMER from Amazon (Sorry, but noobs can post links)
It's compact, uses your existing cable and delivers 12 VDC @ 2 A. Under $10 US.

Aviator47 said:
You might consider the i-Blason 12V 2A MINI BULLET STYLE CAR CHARGER FOR ASUS Eee TRANSFORMER from Amazon (Sorry, but noobs can post links)
It's compact, uses your existing cable and delivers 12 VDC @ 2 A. Under $10 US.
Click to expand...
Click to collapse
It may work, or it may not. Drawing on my experience with the Galaxy Nexus, there were quite a few car chargers that had specs like this but which in fact were seen as "USB" chargers when used with the Nexus, and I suspect would behave the same way with the TF700T.
I am not an eletrical engineer, but it has something to do with how certain pins are shorted or not, and not all chargers that say they deliver the higher amperage will in fact do so with all devices.
It'll just take somebody to buy and try, and report what does or doesn't work. Per my post above, the chargers that work with my Nexus also work with my Tablet, in being seen as "AC" charging.

DLCPhoto said:
It may work, or it may not. Drawing on my experience with the Galaxy Nexus, there were quite a few car chargers that had specs like this but which in fact were seen as "USB" chargers when used with the Nexus, and I suspect would behave the same way with the TF700T.
I am not an eletrical engineer, but it has something to do with how certain pins are shorted or not, and not all chargers that say they deliver the higher amperage will in fact do so with all devices.
It'll just take somebody to buy and try, and report what does or doesn't work. Per my post above, the chargers that work with my Nexus also work with my Tablet, in being seen as "AC" charging.
Click to expand...
Click to collapse
Don
I have one on order and will pick it up at my daughter's when we go to the US next month. Will post what I learn.
HOWEVER - a true "USB Charger" provides a 5VDC output, not 12- 15 VDC, as does the i-Blason unit I mentioned. Note that i-Blason states very clearly, "Warning: Pls do not use with other MP3 or smartphone... High Voltage could cause burn out."
The difference many smartphones (and other USB ported devices) detect in "USB Chargers" versus "AC Chargers" is max current available (<0.5 A vs >1.0 A) For example, I have a USB battery and a video cam that will both fail to illuminate the charging light if connected to a charging source below about 0.75 A, but still charge, albeit slowly. Both came with 1.5 A USB (5 VDC) wall chargers.
Since the i-Blason is a 12 VDC, not a 5 VDC output, the odds are high it will charge the Transformers at a rate very similar to the wall charger. At least based on electrical "theory". If I had to blind pick a third party car charger, the specs for the i-Blason, to include using the stock cable, were what influenced my choice.

Aviator47 said:
Don
I have one on order and will pick it up at my daughter's when we go to the US next month. Will post what I learn.
HOWEVER - a true "USB Charger" provides a 5VDC output, not 12- 15 VDC, as does the i-Blason unit I mentioned. Note that i-Blason states very clearly, "Warning: Pls do not use with other MP3 or smartphone... High Voltage could cause burn out."
The difference many smartphones (and other USB ported devices) detect in "USB Chargers" versus "AC Chargers" is max current available (<0.5 A vs >1.0 A) For example, I have a USB battery and a video cam that will both fail to illuminate the charging light if connected to a charging source below about 0.75 A, but still charge, albeit slowly. Both came with 1.5 A USB (5 VDC) wall chargers.
Since the i-Blason is a 12 VDC, not a 5 VDC output, the odds are high it will charge the Transformers at a rate very similar to the wall charger. At least based on electrical "theory". If I had to blind pick a third party car charger, the specs for the i-Blason, to include using the stock cable, were what influenced my choice.
Click to expand...
Click to collapse
Appreciate the additional info - will be interested to see if it performs as hoped. I suspect it will, especially based on that warning.

[Q] Charger/Charging Questions

I searched through some of the threads and I didn't see one directly related to my question so here it goes. I have been unable to get my tablet and or dock to charge with any other charger other then the one it came with. I'ver tried a samsun tablet charger, an 8w usb charger, other misc wall blocks etc. Will our tablet only charge with the asus charger? Any thought's or ideas on this would be great.

eeeeeeeeek said:
I searched through some of the threads and I didn't see one directly related to my question so here it goes. I have been unable to get my tablet and or dock to charge with any other charger other then the one it came with. I'ver tried a samsun tablet charger, an 8w usb charger, other misc wall blocks etc. Will our tablet only charge with the asus charger? Any thought's or ideas on this would be great.
Click to expand...
Click to collapse
According to some it is possible to use a USB 5V charger to charge but you need the patience of Job and have it shut down. The simplest answer is that this tablet cannot be charged from ANY USB 5V power source.
The tablet charges at 12V 1.2A. The ASUS Charger is wired in such a way that when using the supplied cable it charges the tablet with 12V @ 1.2 A. When any other USB cable is used the charger will output 5V so that it can be used to charged other devices.
The only other source of chargers is from eBay. Just make sure you buy one that puts out 12Volts with a minimum of 1.2Amps.
There are other answers to this same question just maybe not the way you posed it!

eckka said:
According to some it is possible to use a USB 5V charger to charge but you need the patience of Job and have it shut down.
Click to expand...
Click to collapse
Yes, the tablet (but not the dock) will charge from a 5V USB port, but it will be *very* slow (a few % per hour), and the tablet must be in standby or off.
eckka said:
The tablet charges at 12V 1.2A.
Click to expand...
Click to collapse
The original charger outputs 15V.

_that said:
Yes, the tablet (but not the dock) will charge from a 5V USB port, but it will be *very* slow (a few % per hour), and the tablet must be in standby or off.
The original charger outputs 15V.
Click to expand...
Click to collapse
Yes the original is 15V, it does actually switch to 5V if a non transformer USB device is connected. I'll add that a lot of the cheap eBay chargers output 11V to 12V which is why we have so many issues with the device trying to figure out what it is connected to.... imo.

A regular USB charger is 5V.
The tablet starts detecting a charge at 12V.
The original charger is 15V.
It CAN be charged from 5V, but you have to shut it down and it charges at 3-5% an hour. This isn't "some" mentioning it; it's in the bloody manual.
@sbdags If the cheap chargers indeed charge at between 11V and 12V, that explains the constant beeping people experience whilst using them. It keeps varying between "Charging" and "Not Charging".

So basically it sounds like the best way to charge is from the original charger/cable that came with the unit. This is no biggie. I was just trying to understand why a 8v battery back wasn't charging the tablet, but it wasn't idle, i had it on. So if I wanted to use that I would need to power off the device and it will essentially trickle charge. I don't see to many 15v usb car chargers on the market, though I haven't done extensive research. Thanks for the input.

It does charge (slowly) when on and idle - I regularly charge it overnight hooked up to my PC.

Charging Speeds

Hi,
Wanted your thoughts and opinions on charging speeds. I've never actually timed how long it takes to charge. i leave it overnight and it's ready when i wake up.
When i plug the phone into the charger, it flashes up slow charging for 2 seconds then disappears. which got me wondering how much it's actually using.
i used to use Current Widget app on my Samsung S3 which told me exactly how much current the phone was taking from the charger. typically it was 1A via AC/mains and 499mA from a PC. Plugged in to AC, I could play a power hungry game and it would still charge the phone at a good rate.
The LG kernel doesn't like these apps - the mA value is all over the place but it's typically <500mA displayed.
I could buy a USB ammeter to work out how much the USB charger is supplying but do you have any other methods of finding out? Do you know what your phone uses?
at home, i use a Xtrememac dual USB charger, 2x 2.1A output with a shielded 3M USB cable. for those wondering, it's the same regardless what cable i use. Have also tried with generic usb chargers, iPad chargers and official and OEM cables from LG and various other manufacturers. Have also used a data-shorted USB cable from PC which is the same result.
I haven't tried the LG charger yet (mainly as it's a 2 flat-pin plug and i don't know where i put the box) but i think i recall it being a 1.8A charger.

I use an application called "charger report" which can display current consumption and Xtar "USB detector" device. They both show the same numbers. But Xtar USB detector can detect voltage of a charger. The charging current of LG g pro 2 is 1.4-1.5A when the smartphone is not used and higher when I use it. Using USB detector I found out that this smartphone can charge with maximum current a charger can give only if the charger's voltage is 5.3v. So it chargers at full speed with original charger and two other chargers I have: a charger from my Lenovo s6000 (2A 5.4V) and from my Asus t100 (2A 5.3V).

i tried that app too and got the same results as with Current Widget.
i'll buy a "usb detector". thanks.

I forgot to mention that it take approximately two hours for charging indicator to reach 100% when the smartphone reports that it fully charged. And it's necessary to left it connected to a charger for ten to twenty minutes to be really fully charged. Otherwise charging indicator will soon drop to 90%. One can tell if a smartphone is still charging by touching a charger or by looking at current consumption: a charger would be warm and current would be higher than 200mA.

Is the GP2 Quick Charge (1 or 2) enabled? I can't read anything about it other than it's in Snapdragon chipsets. Not sure if it can be disabled or not.

ray-lee said:
Is the GP2 Quick Charge (1 or 2) enabled? I can't read anything about it other than it's in Snapdragon chipsets. Not sure if it can be disabled or not.
Click to expand...
Click to collapse
The Snapdragon 800,801 and 805 is for Quick Charge 2.0
The Snapdragon 600 for 1.0

ok, does anyone use a Quick Charger with their GP2? is it noticeably faster?

not yet available in Austria, I have read it kills the battery life on

ray-lee said:
Hi,
Wanted your thoughts and opinions on charging speeds. I've never actually timed how long it takes to charge. i leave it overnight and it's ready when i wake up.
When i plug the phone into the charger, it flashes up slow charging for 2 seconds then disappears. which got me wondering how much it's actually using.
i used to use Current Widget app on my Samsung S3 which told me exactly how much current the phone was taking from the charger. typically it was 1A via AC/mains and 499mA from a PC. Plugged in to AC, I could play a power hungry game and it would still charge the phone at a good rate.
The LG kernel doesn't like these apps - the mA value is all over the place but it's typically <500mA displayed.
I could buy a USB ammeter to work out how much the USB charger is supplying but do you have any other methods of finding out? Do you know what your phone uses?
at home, i use a Xtrememac dual USB charger, 2x 2.1A output with a shielded 3M USB cable. for those wondering, it's the same regardless what cable i use. Have also tried with generic usb chargers, iPad chargers and official and OEM cables from LG and various other manufacturers. Have also used a data-shorted USB cable from PC which is the same result.
I haven't tried the LG charger yet (mainly as it's a 2 flat-pin plug and i don't know where i put the box) but i think i recall it being a 1.8A charger.
Click to expand...
Click to collapse
Hey ray-lee!
I just bought this phone and as it seems it could get someday similar problems as my former phone the Galaxy Note 2.
That phone has had problems with charger and cable also. I had to buy another set of charger and cable since the original ones gave up a few months after i purchased the phone (it was used). The cable managed only 500mA wich is very slow for a battery that strong. One night was once not enough to charge my phone from 30% to 100%. As it seems it is problematic to manufacture cables, that can hold up and continually grant the 1,8 A that would charge our device in just 2 hours. I read somewhere that the G Pro 2 is one of 5 devices that has blazing fast speeds on charging the battery. If you handle the cables with caution hopefully you will not encounter problems. If so my guess is, that you will have a hard time in finding a cable that can hold up. Sadly the stock cables are always more expensive. I do not get it, why companies dont build travel adapters that only charge ur phones built solid with sturdy cables to ensure the transmission of high currents. That way with charger + usb cable is just stupid, even when tis is an all in one solution.
I like this phone very much and i hope, that the cables will not be that sloppy as the cables that Samsung had/ still has. With Current Widget i get readings around 1500 mA (1,5 A) when connected to the stock charger. And yes the LG Charger is an 1,8 A one. I have also flat pins, but received an adapter to be able to connect it in Hugary.
Just sharing thoughts here, that will maybe helpful to someone...
:highfive:

2amp charger, charges my Pro 2 in apprx 1 hour while my old LG 1amp charger fills it in 1.40 hours apprx

ray-lee said:
Is the GP2 Quick Charge (1 or 2) enabled? I can't read anything about it other than it's in Snapdragon chipsets. Not sure if it can be disabled or not.
Click to expand...
Click to collapse
i "think" as long as device has snapdragon it is Quick Charge enabled

I use the "Charging Report" app on my phone, and it reports proper values.
(Around 1500mAh with the LG charger, and around 1600mAh with the 2.0A Samsung charger.)
If your phone is charging slowly, check the CABLE. Cable can broke too.
(Many people complain about their Samsung charging cables, because they just stop delivering power after a while and just charge the device slowly.)

Anyone tried Quick charge 2.0?? https://www.qualcomm.com/products/snapdragon/quick-charge

enkhtwshn said:
Anyone tried Quick charge 2.0?? https://www.qualcomm.com/products/snapdragon/quick-charge
Click to expand...
Click to collapse
All Devices with the Snapdragon 800 have Quick Charge 2.0!

letschky said:
All Devices with the Snapdragon 800 have Quick Charge 2.0!
Click to expand...
Click to collapse
So anyone tried it? That is the question

Yes, I have the Motorola Turbo Charger.

coastalmikey said:
Yes, I have the Motorola Turbo Charger.
Click to expand...
Click to collapse
How long does it charge from 0-50 from50-100 from 0-100?

There aren't many chargers out there. and the ones that are, are usually US 2 pin. I need a UK 3 pin or travel charger (changeable pins) really.

enkhtwshn said:
So anyone tried it? That is the question
Click to expand...
Click to collapse
To achieve full charging speeds, a Quick Charge 2.0 enabled device must be paired with a Quick Charge 2.0 certified adapter