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.

Can I use a Blackberry Charger to charge my Droid?

My Samsung Droid Charge charger has an OUTPUT of the same voltage and 700 MILI amps.
My Blackberry Bold charger OUTPUT has the same voltage but is 1 AMP output... or 1,000 MILI amps.
If I use the Blackberry charger in my new Samsung Droid Charge will that mess anything up in the Samsung? could it shorten the life of the battery?
Thanks!

sure can, including wall chargers and car chargers

well if the amperage doesn't match exactly couldn't that mess up the Droid Charge?

it should be fine...but you might confuse your phone into thinking that it is a cutting edge smartphone circa 2006

If the power output of the charger you want to use is rated at less than what the OEM one is, you would only damage the charger itself if it isn't made properly.
The phone will pull a specific charge from the charger, say 500mA as an example. If the charger is rated at 400mA and doesn't have wiring to prevent an over-draw, you will damage the charger, especially if you use it for extended periods of time. If the charger does have circuitry to prevent over-drawing power, you'll just charge the phone slower. If you use a charger rated at 1000mA and the phone pulls down 500mA, using a higher rated charger doesn't make the phone charge faster as it will still just pull the 500mA. You'd just be less likely to damage the charger using one rated for more than what the device will accept.

Charge faster
imnuts said:
If the power output of the charger you want to use is rated at less than what the OEM one is, you would only damage the charger itself if it isn't made properly.
The phone will pull a specific charge from the charger, say 500mA as an example. If the charger is rated at 400mA and doesn't have wiring to prevent an over-draw, you will damage the charger, especially if you use it for extended periods of time. If the charger does have circuitry to prevent over-drawing power, you'll just charge the phone slower. If you use a charger rated at 1000mA and the phone pulls down 500mA, using a higher rated charger doesn't make the phone charge faster as it will still just pull the 500mA. You'd just be less likely to damage the charger using one rated for more than what the device will accept.
Click to expand...
Click to collapse
I had purchased a usb cable a couple of years ago on kijiji for my BB bold back then because I didnt have a charger for it. Then I got the S3 and one time I randomly used the BB cable connected to the S3 charger via USB, I noticed the phone charged WAYY faster than the normal S3 cable does. Now I got an S4, and it still charges a lot faster than the normal cable for it. In fact I'm charging both my S3 and S4 at the same time right now, the S3 with normal cable charged from 4% to 15% in the exact same amount of time my S4 charged from 48% to 72% with BB cable. Does this mean I'm damaging my charger that's connected to the BB cable?

FlashThisB said:
I had purchased a usb cable a couple of years ago on kijiji for my BB bold back then because I didnt have a charger for it. Then I got the S3 and one time I randomly used the BB cable connected to the S3 charger via USB, I noticed the phone charged WAYY faster than the normal S3 cable does. Now I got an S4, and it still charges a lot faster than the normal cable for it. In fact I'm charging both my S3 and S4 at the same time right now, the S3 with normal cable charged from 4% to 15% in the exact same amount of time my S4 charged from 48% to 72% with BB cable. Does this mean I'm damaging my charger that's connected to the BB cable?
Click to expand...
Click to collapse
If by charger you mean that little box that plugs into the wall, that is actually a power supply. It just converts 120VAC 20A to 5VDC and whatever current it specifies. Also the stock s4 uses qualcomm quick charge, which means that if you use the stock power supply with the s4, it will charge at up to twice normal speed, provided you have a compatible cable (which it seems the BB cable is).
Sent from my SCH-I510 using Tapatalk 2

USB charger

I tried to charge my A700 with a HTC USB charger, but it didn't work. Can anybody confirm that the A700 only can be charged with the original Charger and not with any micro USB cable?
Sent from my HTC HD2 using XDA

schm1dt said:
I tried to charge my A700 with a HTC USB charger, but it didn't work. Can anybody confirm that the A700 only can be charged with the original Charger and not with any micro USB cable?
Sent from my HTC HD2 using XDA
Click to expand...
Click to collapse
I tried several ones and none worked.

Thanks for confirming, that's really bad news.
Sent from my HTC HD2 using XDA

But this was well known befor the device was available. This is necessary because of the huge power pack.
The original charger can provide 12V and 1,5 A. The USB specification is only 5V and 500 mA.

Did you try to charge the HTC with the acer charger ? you cannont plug it ! they added a pin

Out of couriosity,
in this preview they tell us it would charge on USB???
http://youtu.be/Zy736u97xJA
Not good News at all, im lucky i did not preordered this device, its a no go for me...
Can anyone try to charge over USB while the device is turned off, maybe this works?
Greetz Tokl

Tokl said:
Can anyone try to charge over USB while the device is turned off, maybe this works?l
Click to expand...
Click to collapse
No, it doesn't take any power from regular USB pins.
One has the choice: big power pack or loading by USB. I prefer the running time of this device.
Edit: Loading via USB would take over 24 houres for sure.

Now I found also 12V/1.5A on the right side of the housing of the A700. OK so USB is not for charging.
Did someone already find a car charger I couldn'd find at Amazon. (or should we discuss that in the other thread?)
Sent from my A700 using XDA

schm1dt said:
Did someone already find a car charger
Click to expand...
Click to collapse
Not yet, I think third party suppliers just need a bit more time.

I have a different experience to your's.
I've tested USB charging with two different USB-chargers. One from Nokia (5V, 1200mA) and one from Samsung (genuine SGS2 charger). Both charge the A700 in stand by mode with about 4% per hour and up to 100% battery capacity. The android battery info does not say "charging" but it does!
When the A700 is switched on my 5V chargers are to weak to charge it.

Shudushi said:
I have a different experience to your's.
I've tested USB charging with two different USB-chargers. One from Nokia (5V, 1200mA) and one from Samsung (genuine SGS2 charger). Both charge the A700 in stand by mode with about 4% per hour and up to 100% battery capacity. The android battery info does not say "charging" but it does!
When the A700 is switched on my 5V chargers are to weak to charge it.
Click to expand...
Click to collapse
Nice info, but i guess the charging led is off too ?

Shudushi said:
I have a different experience to your's.
I've tested USB charging with two different USB-chargers. One from Nokia (5V, 1200mA) and one from Samsung (genuine SGS2 charger). Both charge the A700 in stand by mode with about 4% per hour and up to 100% battery capacity. The android battery info does not say "charging" but it does!
When the A700 is switched on my 5V chargers are to weak to charge it.
Click to expand...
Click to collapse
Confirmed
I charged my A700 with my HTC USB charger (HTC TC E250) in standby mode this night. It charged from 23% to 64% in about 10 hours. There was nothing at the A700 that showed it is charging.
To be honest, 4% per hour is "nearly not charging".

schm1dt said:
Confirmed
I charged my A700 with my HTC USB charger (HTC TC E250) in standby mode this night. It charged from 23% to 64% in about 10 hours. There was nothing at the A700 that showed it is charging.
To be honest, 4% per hour is "nearly not charging".
Click to expand...
Click to collapse
This is known as trickle charge. The device might charge if the micro USB provides enought mili amps AND the device does not need much power when connected (i.e. screen off).
I really doubt that the device will charge on USB when the screen is on, but on the other hand the device will definitly discharge slower when connected to USB.
I have a small calculation to explain things:
The original charger operates with 12V at 1.5 Amps = 18 Watts (which is not USB compatible so they hat to change the jack to ensure it will not be pluged in to a normal USB device and damage it)
If you would like to have the same Power over USB with its 5V max voltage you would need at least 3,6 Amps. Now that is far to much for those little pins on the micro USB jack and the currency would damage the pins when pluggin in and out.
USB standard specification normally is 500mA = 0,5 Amps ( -> 2,5 Watts in comparison with 3,6 Amps 18Watts)
So I think Acer has done a quite nice compromise.
Hope that clarifies matters a bit.

ninjaw said:
Nice info, but i guess the charging led is off too ?
Click to expand...
Click to collapse
Confirmed, no charging LED with standard 5V charger. Orange LED while charging only with original 12V charger.

mearoth said:
This is known as trickle charge. The device might charge if the micro USB provides enought mili amps AND the device does not need much power when connected (i.e. screen off).
I really doubt that the device will charge on USB when the screen is on, but on the other hand the device will definitly discharge slower when connected to USB.
I have a small calculation to explain things:
The original charger operates with 12V at 1.5 Amps = 18 Watts (which is not USB compatible so they hat to change the jack to ensure it will not be pluged in to a normal USB device and damage it)
If you would like to have the same Power over USB with its 5V max voltage you would need at least 3,6 Amps. Now that is far to much for those little pins on the micro USB jack and the currency would damage the pins when pluggin in and out.
USB standard specification normally is 500mA = 0,5 Amps ( -> 2,5 Watts in comparison with 3,6 Amps 18Watts)
So I think Acer has done a quite nice compromise.
Hope that clarifies matters a bit.
Click to expand...
Click to collapse
Thanks M8,
this cleares things.
Still waiting for the 3G/4G Device here in Germany
Greetz Tokl

On the A510, when charging the battery via USB, the icon does not indicate it.
That must be the same on the A700.
DЯΦ[email protected]П said:
But this was well known befor the device was available. This is necessary because of the huge power pack.
The original charger can provide 12V and 1,5 A. The USB specification is only 5V and 500 mA.
Click to expand...
Click to collapse
Since USB 2.0 version :
"Several changes and increasing limits including allowing 1.5A on charging ports for unconfigured devices, allowing High Speed communication while having a current up to 1.5A and allowing a maximum current of 5A"
Source : wikipedia.org
Fortunately we are not limited to 500mAh, otherwise we could not quickly recharge our current smartphones .

There are some USB/AC adapters available that put out 2A of juice instead of the typical 1A. For those in the US, check out www.monoprice.com -> they're my go-to source for inexpensive spare cables & such.

It seems that finding a cheaper charger for the A700 isn't a simple task. I had to wade through a lot of cross references with some unintentioned misinformation. First thing was the model number. It's the A510 that is most like the A700 not the A500. Though the A500 does share some similarities it's not the closest match.
When I look for any type of charger, I make sure that the output voltage is correct and the amperage requirements are correct. Looking at the A700's charger, the manufacturer managed to squeeze a lot of info onto it. Amperage is what I always try to find. That is the total amount of current it can handle and deliver to the device connected to it. The A700's charger can handle 1.5 amps. So, the A700 sucks up a quantity of 1.5 amperes of electrons in order for the battery to fill up to it's capacity. That is the load the tablet's battery presents to the charger. Make sure that the charger bought for the A700/A510 can handle at least 1.5 amperes or the wall wart will be OVERLOADED. This is where the charger begins to overheat, smoking warning signals may start coming from the plug and your're asked for a donation for the local voluteer fire department. Besides the voltage which is 12 volts dc, load current requirement is the most important value I make sure is correct for saftey's sake. It is alright to get a charger that has a higher amperage rating but the voltage must be the same, 12vdc for the A700. It just means the charger can handle a larger load.
The only adapter I could find was the original Acer product, mainly because of the unique USB dual purpose connector interface. There is a little diagram of the pinout for the plug on the charger. Using a magnifing glass, I could barely make out the pins the +/-12vdc are attached. Pin P1 is +12vdc and pin P12 is -12vdc. It looks almost beyond a humans capabilities to make or solder together a short plug interface conversion cable in order to use other 12vdc/1.5 A chargers.
I've read in the forums some uncertainty about the proper specs for a replacement charger for the A700, that's why I wrote this post. Maybe , this will help clearup some of the confusion and not add to it. I've also noted a lot of chatter about using a USB cable with the micro USB plug to charge the A700 tablet. Apparently, USB charging can be acheived but it is very slow ( 24 hours or more ) and the amber/white power LED does not indicate the tablet is charging or has finished charging.
If anyone has more info about the A700 charger please reply or post....
Thanks All...

Hi All!
I know that it could be difficult for you to check this Polish site but you can find there a charger that I am going to buy. It has some changeble plugs - also micro usb.
link:
tridex.pl/ramka4.php?menu=towar1&symbol=9396
I think all what you have to do is to look for this kind of a charger - MW3R15GS, btw you can see this name on the original one...
Best regards
Gregork
Acer A701

Save your money and your A701. This thing has only a standard micro-usb plug-in. Check the connector of your Acer charger ... look really close and for better comparison hold a micro-usb-connector from a standard cable next to it. The connector from Acer is longer .. why? because the first row of pins that you can see are not the same ones that fit in a micro-usb-jack. Look deeper into the connector from Acer and you will see a second row of pins.
So if you use this charger with the adapter from that site and set a higer voltage you might fry the usb from your tablet. Sorry to disapoint you but better now than later with a broken tablet.

[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.

[Q] Special Charger

Does this tablet require a special charger as i only seem to be able to get it to charge using the charger that came with it. if i try a power pack or any other charger it will not charge

It requires a 3amp or better charger at the standard 5V. I've successfully used battery banks and chargers that have 3amp or more. Most of the newest chargers and battery banks that support quick charging via the orange USB ports should provide 3amps and work fine from what I've experienced.
Sent from my LGMP450 using Tapatalk

What you might find is that the tablet does not report that it's being charged but it is actually being charged, very slowly and there's no indication of it taking place...
The way to check, is to plug in the tablet and note the battery percentage, leave it charging (with no indication that it is!) and then come back and check the battery percentage, you'll see that it's actually climbing up!
It does take a long time to charge on a 5V USB charger but the reason it doesn't show that it's charging is supposedly because the tablet needs to see at least 12 volts...
I've just ordered a 15v charger on Aliexpress for $5 shipped, to see if I can speed things up.
Still need to sort out the dead dock battery and may well get one from Aliexpress too...