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Sorry if this has already been asked and answered - the XDA Search has been down for the past couple of hours and I just want to be sure I'm not missing anything here..
From what I can see in the reviews, the TF does *not* have any sort of charging indicator / LED on it - correct? I read that there will be one on the keyboard dock - but there is not one on the tablet.
So what are you guys doing? Just plugging it in and letting it sit overnight to give it its full charge - and then going by the battery indicator when you turn it on?
I've got my new TF sitting next to me here, and I'm trying to be a good dad to it by charging it up first before using it - but not having any sort of an indicator on it - I have no idea if it's doing anything or not!!!
Screw it - I think I"m gonna unplug it and start futzing it with it! Battery be damned!!
btw - damn this charge cable is SHORT!!
No charging LED that I can see on mine, and yea, I hate this stupid charging cable, guess you can always get a USB extension cable.
pogul said:
Sorry if this has already been asked and answered - the XDA Search has been down for the past couple of hours and I just want to be sure I'm not missing anything here..
From what I can see in the reviews, the TF does *not* have any sort of charging indicator / LED on it - correct? I read that there will be one on the keyboard dock - but there is not one on the tablet.
So what are you guys doing? Just plugging it in and letting it sit overnight to give it its full charge - and then going by the battery indicator when you turn it on?
I've got my new TF sitting next to me here, and I'm trying to be a good dad to it by charging it up first before using it - but not having any sort of an indicator on it - I have no idea if it's doing anything or not!!!
Screw it - I think I"m gonna unplug it and start futzing it with it! Battery be damned!!
btw - damn this charge cable is SHORT!!
Click to expand...
Click to collapse
Monoprice has the USB 3.0 extension cables, but they won't be in stock until tomorrow (their estimate). When they are back in stock, a 6ft extension will run you about $7-$8 shipped.
I plan to order a few cables from Monoprice with a mini hdmi to hdmi cable.
Does it need to be usb 3.0 or will usb 2.0 do the trick ?
dfin13 said:
Monoprice has the USB 3.0 extension cables, but they won't be in stock until tomorrow (their estimate). When they are back in stock, a 6ft extension will run you about $7-$8 shipped.
Click to expand...
Click to collapse
USB 2 cables don't supply enough power.
It will charge, but I think it has to be off and it'd be really slow going.
But usb 2.0 extension cable will work fine with the supplied charger? Also would you not require a usb 2.0 to usb 3.0 converter ?
Asus really overlook the inclusion of an charging indicator. Or, they are trying to make more $$$ on the keyboard/dock?
jake21 said:
But usb 2.0 extension cable will work fine with the supplied charger? Also would you not require a usb 2.0 to usb 3.0 converter ?
Click to expand...
Click to collapse
Has anyone got some definitve experience on USB2 vs USB3 for charging and/or with an extension cable. The whole charging process and adaptor are making me a little nervous in general.
there is no reason to invest in USB 3 gear when all you really need is higher amperage, wich you often get from stand-alone chargers like the one supplied or you can buy in stores (just check that the output is 1000mah or more, 2000 mah is desired for effective charging).
The reason you might want to use a usb 3 PORT (cable makes no diffrence) is that usb 3 deliver more juice then usb 2, but unless it is a dedicated charger port that can supply 2000mah+ charge the port still require you to have the pad either off or stand by and even then charging will take ages.
Consider this, the supplied charger delivers 2000mah on 5v and my HTC charger to my phone has 1000mah @ 5v. Compared to the standard 550mah on a singel non-charger adapted USB port on a computer.
The TF charger output at 15V @ 1.2A with using the supplied USB3.0 cable. If you use a USB2.0 extension cable, it will drop the charging voltage down to 5V. You will need a USB3.0 extension cable
eli.kennedy said:
Has anyone got some definitve experience on USB2 vs USB3 for charging and/or with an extension cable. The whole charging process and adaptor are making me a little nervous in general.
Click to expand...
Click to collapse
There's a thread about this issue here. Several USB 3.0 cables have been found to work, but not for everyone. I have this one that I received today. It charged both the tab and the dock with the wall charger. I've also got a Tripp Lite that's worked for others on the way in the case the other didn't work.
it has to be USB 3.0 extension since the tablet recognizes the extra pin which is what lets it charge at the full rate.
jmkhenka said:
there is no reason to invest in USB 3 gear when all you really need is higher amperage, wich you often get from stand-alone chargers like the one supplied or you can buy in stores (just check that the output is 1000mah or more, 2000 mah is desired for effective charging).
The reason you might want to use a usb 3 PORT (cable makes no diffrence) is that usb 3 deliver more juice then usb 2, but unless it is a dedicated charger port that can supply 2000mah+ charge the port still require you to have the pad either off or stand by and even then charging will take ages.
Consider this, the supplied charger delivers 2000mah on 5v and my HTC charger to my phone has 1000mah @ 5v. Compared to the standard 550mah on a singel non-charger adapted USB port on a computer.
Click to expand...
Click to collapse
Not quite correct. The charger senses a gnd connection on pin 7 of the USB 3.0 connector and delivers 15V @2a to the TF and or Dock. There are only 4 conductors in a USB 2.0 Cable. so the charger only delivers 5V as it does not see the gnd on pin 7. For all the technical details see the thread started by DevCake where the voltages and currents have actually been measured. A 5V 20A charger will not be as good as one with 11-15V at about 2A as the charger is not a constant current charger but a power source for a charge controller ( controlling the current) in the TF.
I appreciate that it is a slightly older thread and not sure if what I'm about to post is already known by TF owners but here goes anyway.
The discussion has moved on to cables but the threqad title is about a charging indicator. I've discovered that the battery icon in the bottom RH corner has a lightning symbol through it when it is being charged.
Sorry if it's old news but I've only had my TF one week and thought other users might not be aware
Really wish they would have put in a fancy multicolor LED somewhere on the housing but we can't win them all. Even the Nook Color had an LED on the cable itself.
Hello everyone, I just have a question in regards to USB fast charging for the Galaxy Nexus.
I'm about to install a JVC head unit in my car (model KD-R810) and it proclaims to have 500ma available for charging Apple devices. My fear from my research is this will not be enough power to charge my Nexus while using GPS, so I am looking into other methods.
What I am thinking to do is use a Sirius car charger that is no longer needed (that puts out 5v 2a charging capability) and use this to keep the phone charged.
Now my question is, if I have the data portion of the USB cable connected to the above mentioned car stereo head unit and the power portion of the USB cable connected to the Sirius charger, can anyone suggest any reason why this is not a good idea?
Also, will I need to trick my nexus into charging "AC" rather than "USB" even while connected to a USB charger that can supply 2a?
I've read articles about having to short the data lines on a USB to get it to charge in AC..?
I am wondering if doing something like this is needed? I currently have a rocketfish charger rated at 600ma that charges the nexus in "AC" mode, however I'm wondering if having 2a available using the Sirius charger will charge the phone that much faster, or if this is dangerous for some reason? I did read somewhere that the nexus will only draw as much power as needed and should be safe with higher rated chargers, however I wish to confirm before risking frying anything.
So my question is, if I wanted to use my Nexus with GPS and with my above mentioned JVC stereo as a storage place for music, would I benefit from using a hacked cable on a switch for example to be able to switch between GPS charging mode and "Data" mode for use with the head unit?
Perhaps a switch for the data portion of the USB to switch between going to the headunit and being shorted for fast charging?
Any guidance would be appreciated!
There is a kernel patch know as Fast-charging. It's implemented in Matr1x and air kernel i believe. This should do the trick.
Sorry i didn't see this before, don't know how i missed it. Here is the rundown:
-Data mode uses 500mA
-AC mode exceeds this, stock charger rated at 750mA
-Excess amperage should be limited by the Nexus S with no problem
-FastCharge forces AC mode, so the phone will attempt to draw the max current it can handle. NO DATA TRANSFER is available in this mode, so can't use it as a USB for your deck
Essentially, i would be using a kernel with FastCharge with the 2A charger and get the Nexus S to decode and output music through a 3.5mm jack to the AUX input on the deck. I hear it can get quite hot while charging and using GPS, so make sure to check it's heat every so often just in case. Decoding music will put practically no extra strain in comparison to everything else it'll be doing, it won't slow the charging by any noticable amount.
Heat can be a problem when using GPS and charging at a high current, my NS gets hot doing these two things at same time!
Try putting the device near a cold air flow inside the car.
Morning All,
Having a problem with charging via MHL adaptor - I have my phone connected via MHL to a Pioneer AppRadio2. Getting the error message saying the phone is drawing more current than the charger can provide, so over a long journey - the charge drops significantly.
I have done some research and found when using and MHL adaptor, the phone sees it as charging via USB which has a max draw of 500MaH. I am currently using a 2amp charger but the phone cannot draw this current due to its own software limitation. It is possible to bridge (short) the 2 USB wires in the cable (data in/out) to trick the device into thinking it is a AC charger. Unfortunately this is not a suitable solution because the 2 USB wires are used to transfer data to the MHL adaptor.
I have found some kernels remove this limitation, or make the phone think all chargers are AC chargers. Does anyone know how which kernel can do this and would be compatible with Android Revolution 6.6.7 (current ROM). Important thing is that video out still works, and also that the phone actually charges!
Any help would really be appreciated!
Modified Faux kernel has this, you can find it here. I'm quite satisfied with it.
There are probably other kernels that have this, Bricked perhaps, but I'm not using them so I can't confirm
With the advent of the S4, and its higher capacity battery, one could understand a higher charging current. However, I seem to have uncovered some findings that the charging system on the S4 is a bit more complex than first thought!
This is a bit techy, and assumes you have a basic amount of electrical knowledge, ie voltages, currents, resistance etc., but I'll try and keep it as simple as possible for anyone who may not!
To explain: The mains charger supplied with the S4 is a model number ETA-U90UWE, rated 5V @ 2A. However, the phone will ONLY charge at full current (which as I have measured so far, depending on what the phone regulates it to, typically sits in the region of 1.2 - 1.5A), when using the supplied charger (or possibly one of equal or higher current rating, depending on how it's configured internally), AND the supplied usb cable, OR any other usb cable, provided its shielding (the metal outer surface of the connectors) is connected at BOTH ends of the cable. Use a cable that doesn't have this shielding, and the charge current drops, regardless of whether there is plenty of current available or not. Use a different charger with an unshielded cable and the current drops even more, again regardless of whether it can supply plenty more current.
My assumption on this, is possibly an effort by Samsung to avoid the scenario of sticking 1.5 amps down a flimsy cheapo cable, the wires of which will likely be too thin to carry it.
After doing some probing around with a meter, I have managed to find a slight difference with the charger itself, compared to a generic one. In a generic one, the two data pins are usually just shorted together, which tells most phones that it's a mains charger rather than a USB port. On the Samsung one on the other hand, the pins appear to be shorted together, and also connected via resistors across the supply line (known as a potential divider), which holds these shorted data pins at a certain voltage. This is what tells the phone what sort of charger it's connected to.
Attached are a couple of diagrams to show the difference between the two chargers. There are in fact various setups of resistors that different manufacturers use to set the charging current, so it's quite easy to run into compatibility issues!
To make this a little less confusing I have done some preliminary experimenting, and I set out my results here.
For the test, I used combinations of 4 different usb style mains chargers: an apple iPhone one rated at 1A, an iPad one rated 2.4A, an HTC 1A one, and the genuine S4 one. With these I used two cables - the supplied Samsung S4 one (which is shielded), and a cheap generic one (which isn't). I started by measured the charging current directly with a meter, by using a very short usb breakout lead I've made, enabling me to interrupt the 5V line. However, I soon noticed that the use of any extension cables, even shielded, can lessen the chance of maintaining a good shielding connection, so I continued the exercise relying on the "galaxy charging current" app to get a reading.
Charger.................... Cable................ Current (A)
=====================================
HTC 1A.................Generic..................... 0.5
HTC 1A.................Samsung S4..............1.0
Apple 1A...............Generic......................0.5
Apple 1A...............Samsung S4..............1.0
Apple 2.4A............Generic......................0.6
Apple 2.4A............Samsung S4..............1.3
Samsung S4.........Generic...................... 0.8
Samsung S4.........Samsung S4...............1.3
So as you can see from these results, the original charger makes a difference, and the supplied cable (or a good quality shielded one) makes a further difference. If you have any further findings please feel free to add them here.
I can see that this is going to confuse some people, as it has me, as I'm sure some will inevitably try charging up their phone on generic chargers/leads at some point, with potentially long charging times resulting!
.
Very nice findings! Thanks for sharing them.
Not only what you say about longer charging time, but also discharging may occur (it has with me) while connected to the USB. I left my phone with USB tethering and it shut itself down after a couple of hours (it was low on battery already). I wanted to keep all the accessories in "new condition" in case I sell the phone in a few months, but I guess this justifies using the official charger and usb lead.
I hope someone can shed some light on the detection mechanism or the particular characteristics of the official cable so it can be replicated in generic ones.
From your findings, also Appe 2,4A charger has some control on the cable used, thanks.
Yes, but you won't be able to get more than about 0.75A out of it even with the samsung s4 cable.
You could try to add an extension cable to check if the charging system needs exclusively an original samsung cable from the charger to the phone.
Original samsung charger => extension cable male/female => original samsung cable => phone
PS: is there an app to check the charging current?
My experiments used an extension cable, that's the one I made into a breakout cable. So no it doesn't change by adding a cable.
There is an app, called galaxy charging current, which I tried also. In the 0.75A results above it showed a max permissible current of 1000mA, with the fully samsung setup it showed 1900mA. In the lower scenarios is showed up as 460mA. Other than that it doesn't tell you anything, it literally just shows you a max possible current, not the actual current it's drawing.
I've found out what the issue was, my generic cable was obviously a cheap one and wasn't shielded! I have edited my original post to re-explain.
Also I did a further test on a PC usb port - the Samsung cable allowed for 500mA, but the unshielded cheap one only allowed about 350mA, so (as pintycar found out), the phone actually carries on discharging in this case!
Interesting post.
I've been trying to mod a car charger so that the s4 draws more than 300mA so far unsucessful. I'm going to add in the 82K resistance and see what happens.
demusss said:
Interesting post.
I've been trying to mod a car charger so that the s4 draws more than 300mA so far unsucessful. I'm going to add in the 82K resistance and see what happens.
Click to expand...
Click to collapse
Hi,
Using a 5a digital bench power supply, I took a normal micro USB cable, cut it in two, added in the 82k resistors and tested.
Before: 450ma, after 1.73a
Then using a clamp meter I tested it with a 2amp Asus tablet charger - it varied between 1.48 and 1.61 amp.
I have since built a few more cables - one to use in my car (again 2 amp charger).
All in all, it works very effectively. Thanks for the initial research (saved me having to open my charger.)
BTW I suspect it is the charger where the resistors are, not the cable, otherwise the phone would try to pull 1.5a + from a laptop if you connected it.
Left my samsung cable at work so will test it tomorrow (if I remember)!
W.
Interesting. So basically for us laymen, you are telling us to use the original charger and cables to the extent possible ... right?
Can you clarify to me what an unshielded cable is? Maybe with a picture? I've got a blackberry's cable at work connected to my PC.
At home, I also have a cable and charger that I got with my Nexus S (I think this says Output 5.0V ~ 0.7A).
Would this be a problem or can I get by with these?
Thanks
I've been using the Samsung cable+charger+USB extension cable and charging the S4 usually takes about 4 hours, I'm going to try with just the Samsung cable next time and see if it makes any difference since people are saying that theirs can be fully charged within less than 3 hours.
Paparasee said:
Interesting. So basically for us laymen, you are telling us to use the original charger and cables to the extent possible ... right?
Can you clarify to me what an unshielded cable is? Maybe with a picture? I've got a blackberry's cable at work connected to my PC.
At home, I also have a cable and charger that I got with my Nexus S (I think this says Output 5.0V ~ 0.7A).
Would this be a problem or can I get by with these?
Thanks
Click to expand...
Click to collapse
Hi,
I believe (guess work here ) that only the original charger "needs" a shielded cable - could be checked by shorting the ground and shield on one side and see if it works at the higher current - if I am bored I may do it - it probably checks the shield and limits the current if it is not there (note I have not tested this so only going by the first posters findings).
BTW a shielded cable has a wire mesh around the 4 internal cables - this mesh avoids external interference messing with the signals. Can't see it affecting the charging though BUT shielded cables tend to have thicker internal cables so could be related to this.
I have it charging at 1.7a on an unshielded cable (thought he power strands are thicker than average) Shielding should only affect the data transfer speed, not the charging current.
If the Nexus S has only a 700mah charger then this will not be able to provide enough current for high speed charging and could easily burn out - nice smell, dead charger, not much else. therefore only use a normal unmodified usb cable (and it will charge at about 450mah).
W.
all this would eexplian why the charger that camewith my S2 dosen't appear to charge my phone fully over night...
For what it's worth I'm charging with a Note 1 charger...a thick shielded cable via the S3 docking station....and getting 900mah...
will get my original cable tonight and have a go tomorrow...
interesting read, my s4 lead and charger are still in the box and I'm using my nexus 10 ones phone charged from about 30% to full in just over 2. may have to change the old HTC £2 lead I've got connected to my works pc then, maybe why it's struggling to charge when playing music. guess this is one way to get people to buy more expensive cables
Very interesting read, thanks TS.
My original charger and cable set is still in the box; I've been using my Mom's old Galaxy Note charger.
I'll try the original cable + wall mount and see how fast it is compared to my current charger.
wmccann2 said:
Using a 5a digital bench power supply, I took a normal micro USB cable, cut it in two, added in the 82k resistors and tested.
Click to expand...
Click to collapse
Can you show me your final cable with a pic? Thanks
After this thread I have stopped using my blackberry bold cable to charge s4 and of course the cheap one too.. thanks op!
Sent from my GT-I9500 using xda app-developers app
I'm not sure if shielded vs. unshielded is the difference - probably wire gauge is the difference.
For example, if you shop at Monoprice, you have two options for USB cables: 28 gauge cables, and 24/28 gauge cables.
For wire gauge, lower is larger - the 24/28 gauge cables have thicker wires for the + and GND lines. A pure 28 gauge cable is likely to drop voltage a bit at high currents, and my observations have been that most newer devices, ESPECIALLY Qualcomm-based ones, are VERY finicky when it comes to input voltage drops.
As to the charger itself:
Apple chargers are almost guaranteed not to charge at full current, as they don't conform at all to the USB battery charging standard. Some newer Android devices do have at least partial detection of Apple chargers, so they may charge at 1A if an Apple charger is detected (any Apple charge, even 2.1A ones).
It sounds like the included official charger is a tablet-compatible one. Samsung tablets expect D+ and D- to be held by the charger at 1.2 or 1.8 volts (I forget which). As a result, Samsung tablets will not charge from standard chargers (like an N7 charger), but standard devices (like an N7) will charge from Samsung tablet chargers.
Now, the question is: Does the GS4 *require* a Samsung tablet-style charger, or did Samsung just include a tablet-style charger because it's backwards-compatible with standard devices? (less part numbers to track in inventory).
A useful pair of points would be: Using the same cable, does the Samsung charger behave significantly different from a Nexus 7 charger?
wmccann2 said:
Hi,
Using a 5a digital bench power supply, I took a normal micro USB cable, cut it in two, added in the 82k resistors and tested.
Before: 450ma, after 1.73a
Then using a clamp meter I tested it with a 2amp Asus tablet charger - it varied between 1.48 and 1.61 amp.
I have since built a few more cables - one to use in my car (again 2 amp charger).
All in all, it works very effectively. Thanks for the initial research (saved me having to open my charger.)
BTW I suspect it is the charger where the resistors are, not the cable, otherwise the phone would try to pull 1.5a + from a laptop if you connected it.
Left my samsung cable at work so will test it tomorrow (if I remember)!
W.
Click to expand...
Click to collapse
I missed this post on my first read-through: What happens if you just short D+ and D- when using the bench supply?
Hi,
I would like to create list of car chargers that are able to charge N5 in AC mode.
Till now I have found only one review on Amazon on: "PowerGen Dual USB 3.1A Car charger".
Sorry, but I still can't post links.
I want to buy something that works for sure.
So, please share your real life experience...
armourer1 said:
Hi,
I would like to create list of car chargers that are able to charge N5 in AC mode.
Till now I have found only one review on Amazon on: "PowerGen Dual USB 3.1A Car charger".
Sorry, but I still can't post links.
I want to buy something that works for sure.
So, please share your real life experience...
Click to expand...
Click to collapse
I got this one http://www.amazon.co.uk/Anker-Dual-...5839252&sr=8-1&keywords=anker+usb+car+charger is working fine, it has 2 ports one of which says it is for apple but works just fine on any device both ports charge over 2 Amps.
Ady1976
Thanks for replay,
Can you please Goto Settings -> About -> Status -> Battery Status: and verify that you see Charging (AC) ?
I am also able to charge with old Griffin charger, but it only works with "Charging (USB)" - 0.5A.
Thanks...
armourer1 said:
Ady1976
Thanks for replay,
Can you please Goto Settings -> About -> Status -> Battery Status: and verify that you see Charging (AC) ?
I am also able to charge with old Griffin charger, but it only works with "Charging (USB)" - 0.5A.
Thanks...
Click to expand...
Click to collapse
Hi, yes it does say charging by (AC)
Ady1976
Thanks a lot !
Now I have one more charger to choose from -
0.5A is USB level so that's why that one doesn't work, anything that charges at 1A or over should be fine.
b1g1an said:
0.5A is USB level so that's why that one doesn't work, anything that charges at 1A or over should be fine.
Click to expand...
Click to collapse
My charger is capable of driving more than 0.5A, but the phone don't "understand' it.
Android determines that a charger is a wall charger (as opposed to a computer) by the fact that the data ports are shorted together. Apple chargers don't do this, so most chargers made for Apple products will only charge Android devices at 0.5A. Heck, almost no car chargers do, unless they were made specifically for an Android device. Here's what I did:
I ordered this Griffin car charger, mainly because of the size. It just BARELY sticks out of the car's charging plug. Then, I ordered the Nexus Wireless Charger, and used the cable it came with (minus the wall plug). Presto... Qi wireless charging in my car. The magnets hold the N5 in place nicely so it doesn't slide off the charger in my center console, and the charger I linked easily supplies the 1.8A that the Nexus Charger expects.
The catch is that this charger was designed for an Apple product, so I had to carefully pry it apart and short the center two USB pins with solder using a soldering iron (those are the data pins).
EDIT: I should point out here that the Nexus charger may work fine without shorting the pins. I didn't test it. I wanted the ability to quick charge via cable if necessary, since Qi charging is a bit slower, so I shorted the pins, but if all you're interested in is Qi charging, you may be able to get by without modifying the charger. If someone wants to test this, please let us know.
jt3
Thanks for the info. I have some kind of Griffin charger with 2 USB ports.
So, I will try to do the same - shorten data pins inside the charger.
I will post it works
Just an FYI, I was charging with a charger that listed AC mode last weekend yet it wasn't charging faster than the power was draining.
Not all the AC modes officially charge at a faster pace unfortunately. My Galaxy Nexus car dock charger though did charge it at a proper AC pace.
What took me a little while to figure out is that this issue may not be as related to the charger as it is to the cable. I tried 3 different car chargers and none of them would keep up with GPS battery drain in the car. I figured out that common to all 3 chargers that I was trying was the cable. So I bought this cable and now all 3 of the same chargers work great. I am finding that even at 1.0A you can keep up with the gps battery drain. At 1.5 amps or greater you can charge the battery in the car while using GPS full time.
http://www.amazon.com/gp/aw/d/B0088HTYUE/ref=ya_aw_oh_pit
jalanjkcarp said:
What took me a little while to figure out is that this issue may not be as related to the charger as it is to the cable. I tried 3 different car chargers and none of them would keep up with GPS battery drain in the car. I figured out that common to all 3 chargers that I was trying was the cable. So I bought this cable and now all 3 of the same chargers work great.
Click to expand...
Click to collapse
This is because some "charge only" cables don't have data pins at all (usually, because they came with a charging dock of some sort, or were designed for devices other than Android). Remember, I said earlier that Android notices that it's on a charger when the data pins are shorted. If they're missing completely, then it will only charge at 0.5A.
My rule of thumb is to stay far - far away from charge-only cables.
I bought a "2.1A Car Charger" with a single USB port (made by PNY....Amazon for about $6 shipped)... opened it up and soldered a bridge between the middle 2 USB pins.
Previously it reported Charging (USB), now I get Charging (AC). Confirmed with a widget that showed charging amps, the number went way way up.
Presumably any of these chargers claiming high-amp output will only work with iDevices, I guess they ignore the USB standard that if the two middle pins are bridged, its a power-only connection and full power can flow.
I did test this on an HTC One X running 4.2 and it reports Charging USB though, so there is a dependency on one of the newer Android kernels (my N5 runs 4.4.2)
Edit: oh yea... with my newly modded charger, I tested turning on Bluetooth streaming audio to my car, GPS on, navigation running, screen on, 100% bright, and wifi tethering enabled, and i STILL had a net charge going.
I've just bought a Blackberry Premium In-Vehicle Charger and my N5 recognizes it as an AC charger. The phone pulls around 1A from it (it's good for up to 1.8A). This is it, though I purchased mine from a local store.