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Hi, I'm really a noob when it comes to electronics. For all I know, when a cable fits it should work
I have a couple of microUSB chargers laying around. They all have an output of 5 Volt but they output a currency that differs from the standard charger (1A).
What is the "golden rule" wrt currency? Are chargers with a currency that is less than 1A save?
current is not pushed, it is pulled by your device as necessary. voltage is pushed, so correct voltage,5V in this case, is very important. As for the current, if the charger can't supply enough current with that voltage it will get hot and cause problems. i.e., you should have a current greater or equal to your original charger and same voltage. this applies to ALL of your electronics.
ozkaya said:
current is not pushed, it is pulled by your device as necessary. voltage is pushed, so correct voltage,5V in this case, is very important. As for the current, if the charger can't supply enough current with that voltage it will get hot and cause problems. i.e., you should have a current greater or equal to your original charger and same voltage. this applies to ALL of your electronics.
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Thank you very much for this explanation. What do you think, a 5v charger with a current of 850mA will that cause big problems when I use it just accidentally to charge my device.
appelflap said:
Thank you very much for this explanation. What do you think, a 5v charger with a current of 850mA will that cause big problems when I use it just accidentally to charge my device.
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It probably wouldn't be a lot of problems, if you really have to do it, charge it when the screen is turned off, so that you will need less current.
You can charge without risk with any USB charger. Unless the charger "signals" that it can supply more than 500mA by having the 2 USB data pins shorted, the HD2 won't pull more than 500mA, which is the minimum a USB charger must be able to supply.
"Golden rule" - If You have 5V its safe for Your phone, current level is determining the time that You need to charge battery.
Kilrah sad that HD2 'pull' no more than 500 mA - ok, if this is true ( i believe it is , he always make some test for it ) original charger needs about 2h, with 250 mA charger it will take more than twice of that time - 4h ( it's not fully linear )
@Kilrah - did You test what's power ( current taken ) consumption during charging ? it's really only 500 mA ? if so, than why HTC use 1A charger ? usually safety rules are about 15 - 30% more than max current needed.
0.5 A + 30% = 0.65A , so why 1A ?
The minimum current what HD2 accepts is 500mA because this is the USB standart.
If the supply could deliver more than 500mA the HD2 will take it up to 1000mA. The maximum current which the HD2 can use is 1A (1000mA).
So if your charger can deliver 5V and 2000mA the HD2 will limit the current to 1000mA. So you can use a charger, when the voltage is 5V and the current at least 500mA.
The push pull principe in the post before is correct, because the charger is a voltage source and not a current source.
I am already enjoying the benefits of proposed standardisation of phone chargers to micro usb pin. Since I upgraded with HD2 from Nokia N97 I am using the nokia wall chargers as well as well as car charger. I didnt have to buy new charging accessories for this mighty HD2.
By the way would the Nokia data cables (micro usb) be able to sync data when used with HD2. Havent tried yet.....
afropolak said:
@Kilrah - did You test what's power ( current taken ) consumption during charging ? it's really only 500 mA ? if so, than why HTC use 1A charger ?
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As said, IF the 2 USB data pins are NOT shorted (that's how it is by default on <500mA/3rd party chargers, or on a PC), the HD2 will limit the current it pulls to ~450mA.
IF they are shorted (on chargers that support higher current like the supplied one) the HD2 will pull more. With the supplied charger it's about 850mA, with a 3rd party "800mA" Chinese charger that didn't have the pins shorted but was modded to have it done, it pulls about 650mA.
PlayStation said:
By the way would the Nokia data cables (micro usb) be able to sync data when used with HD2. Havent tried yet.....
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Micro USB is a standard, so every micro USB cable should be the same. If not, you've got a botched knockoff.
so how do you short the cable assuming I get a car charger without a USB to micro USB cable and sourced my own cable from a parts bin that was probably for computer usage?
cheahcl said:
so how do you short the cable assuming I get a car charger without a USB to micro USB cable and sourced my own cable from a parts bin that was probably for computer usage?
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I don't think that would be a good move!
You would have to be certain of the regulation circuitry of the charger and it's ability to cope with the attendant initial draw of the battery when plugged in.
This will depend on the state of drain of the battery and the various functions in operation at the time on the phone.
At the moment of plugging in is when the draw will be highest and when any protection circuitry will be essential.
A well topped up battery will "draw" less than a depleted one and will continue charging on as little as 350mAh (again depending on what is running on the phone).
A very depleted battery may well not even start the charging process at such a level. That's why the HD2 comes with a 1000mAh wall charger!
The levels quoted for PC/Laptop USB power are nominal off load levels and will vary depending on any othe devices plugged in on the same bus supply.
So, with a PC that has a few attached USB devices, you may well NOT see 500mAh and as has been reported before, you can get battery depletion back into the USB port as other devices draw from the phone!
Always best to keep the battery topped up to prevent "charging strain" on the cells. This will maximise the capacity available when you need it for those longer periods of time.
Just reading up on USB chargers, and I found somewhere in a thread here about phones defaulting to smaller ma when charging via USB if the connector didn't have the data pins shorted or something.
So, I was wondering a couple of things:
1) If the default charger supplies 700ma, do you think that is the most the Nexus S can draw? Does anyone have one of these shorted USB chargers? Does it charge the NS faster?
2) If it does charge faster, how hard would it be to do something similar to shorting the data connections? I have a generic AC-USB cable which I currently use for my iPod touch.
3) Is there a way to check if it is already shorted out? The USB charging port looks similar to ones on my computer, but I'm not sure what to look for.
Thanks for any help! Maybe if we can sort out this stuff, we can provide a solution for those looking for faster charging!
it does work safely, i'm using a 1000 mAh charger at home, and a 2000 mAh charger in the car both are from aftermarket eBay/DealExtreme charges.
no overheating
and charges faster than stock
AllGamer said:
it does work safely, i'm using a 1000 mAh charger at home, and a 2000 mAh charger in the car both are from aftermarket eBay/DealExtreme charges.
no overheating
and charges faster than stock
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Ok thankyou for that AllGamer, I'll think of possible ways I could mod the charger now
The only reason it is slow is because of the USB charging brick instead of just a charger.
Sent from my Nexus S using XDA App
I know it's a wrong thread, but anyone has any pointers as to how to short a regular USB cable to make the phone think it's a power adapter cable?
XBOHDPuKC said:
I know it's a wrong thread, but anyone has any pointers as to how to short a regular USB cable to make the phone think it's a power adapter cable?
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Nah it's not the wrong thread that was one of my questions! I'm not sure exactly where you would do it, but maybe if you skinned the wire, then cut the data lines it would work?
Not sure which end you would do it on however, but that may not matter. Any other ideas?
The two center pins in the USB carry the data. If you pull them out, the cable won't be able to connect to the computer.
Sent from my Nexus S
Wow - you don't need to do this and you wouldn't want to in a computer anyway.
The USB specification says that 500ma (@ 5v) of current should be available from a computer's USB port. Of course, the actual wires can carry much more than this, so manufacturers can tell their phones to takes as much current as is offered.
Almost all computers limit their USB power output accordingly - this is why some opld usb-powered external hard drives needed 2 USB plugs to get enough power. The only computers that I am SURE emit significantly more than 500ma on their USB ports are first and second generation MacBook Airs.
Some phones, the N1 and every other HTC specifically, look for a specially shorted cable to "know if they are plugged into the wall adaptor" as opposed to a computer USB port. In reality, this is just a way to make you specifically buy HTC chargers as opposed to third-party off-brands, because plugging one of these phones into an off brand charger will limit the current draw to about 450ma.
If you want to know if your Android phone thinks that it is in "USB" mode or in "AC" mode, just plug the phone in, open the dialer, enter *#*#4636#*#* and then select battery info. If your phone is one that cares (not all do), it will say USB if it thinks it should be in USB charging mode, or AC if it thinks it should be in AC charging mode.
I would not try shorting out the middle pins in a cable and then plugging it into the computer. First, most will probably just disable the USB port completely, shutting off even power you could draw. Second, if it doesn't shut down, you run the risk that a badly-built USB port might not properly limit the current to 500ma - and since they are not designed to furnish more current than that, you might melt something expensive or start a fire. third, if you make a mistake, you risk shorting out either your phone or your computer, which might ruin your day, week or month, depending on your financial means to replace the system that cooks itself.
I would just run out to your local store, pay 15 bucks for a 2A third-party usb charger brick, and go to town. That will work perfectly - this is what I use, and it probably cuts the charge time by 30-40%. Obviously, this indicates that the NS is not capable of drawing a full 2A - I have not put a meter on it, but I would bet that it limits itself to somewhere just under an amp in.
I have recently bought both a 2A wall charger and car charger and my phone does not recognise either of these as anything more than a 500mA source.
Is it really just a case of opening the car charger up and shorting out pins 2 & 3? they are currently not connected to anything in the charger.
If it's indeed a matter of shorting the data lines, then I think you can skin the wire as suggested by others, but then cut the data lines, short the end that leads to the phone, leave the end to the computer open. I think it's the phone that tries to determine whether the data lines are shorted.
Edit: Can someone measure the continuity between the data pins with the stock charger? I wonder if they are shorted. I'm still waiting for my Nexus S to arrive, so can't test it.
Yup, the data lines in the stock Nexus S charger ARE shorted.
I just modified a cheap 1A car charger by popping it open, soldering the 2 data lines together and putting it back.
The report on the Nexus S before I did this (*#*#4636#*#*) said "USB", and afterwards it now says "AC".
I will report back after I make a road trip if this improves the GPS + Pandora + Screen in car situation. I suspect it will.
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Yup, the car charger seemed to actually maintain and increase the battery this time. Seems good.
The NS supports chargers output to a max of 1000mA, as it says on the back of it, where the battery resides.
Iam using the Dell Streak 7 as a sat nav system in the car. Ive tried to charge it up on the usb car adapter but it seems to loose its charge over time, making the D7 unusable for the purpose of a sat nav. Am i doing something wrong or is there a special usb car adapter for the job?
Thanks, David.
Does it say it's charging when plugged in?
Depending on how powerful your charger is it's likely that it's draining faster then the charger can provide. At best on my s5 it's just barely faster then the charger and the s7 needs more power then that.
Thanks for peply, yes it states it is plugged in. I came to the same conclusion. Wonder if there are any other chargers that have more juice.
diddy64 said:
Thanks for peply, yes it states it is plugged in. I came to the same conclusion. Wonder if there are any other chargers that have more juice.
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There are several that will do the job. Just look for specs that include putting out 5.5 volts and 2 amps. Several of the chargers that are made for the iPad2 will work. And you may want to install a lighter adapter that you can wire directly to the battery that will allow up to 2 or 3 amps from each port
Most standard USB ports do not put out enough power to charge the DS7. The best bet is to use a inverter that plugs into your cigarette lighter and then plug the charger into that, not just the USB cable.
http://www.amazon.com/Power-Inverter-Charger-Portable-SmartPhones/dp/B00144KS6W
I use this setup:
Bestek Adapter
Trans4m lighter adapter
The Bestek I have wired to the battery so I have no fuse problems with lighter, and with that I can charge either my iPad2 or my Streak7, IF I need to charge both, then I plug the Transform adapter into the Bestek and can then charge BOTH devices, the Ipad2 AND the Streak7 and a couple of other things if need be
Thank you guys, this gives me alot of hope. Once again you all get my thanks.
Cheers,
David.
Yea, like they previously stated not all chargers are created equal.
Unless it states it's a tablet/ipad charger you cant assume it's doing 2+ amps. Most phone/lower end ones can only do 500mA/1A.
Realistically you'd prob need at least 2 amps to get a net gain while using gps/anything demanding. But I dont know if it would even try and draw above that if given the chance. [email protected] is what the bundled wall charger does and can accept up to 5.5v (as it's still within the +/-10% tolerence of the usb spec, but just barely)
My fully charged stock S7 WiFi running 514 draws only 45-70mA. Maybe starting fully charged would help?
wptski said:
My fully charged stock S7 WiFi running 514 draws only 45-70mA. Maybe starting fully charged would help?
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I don't know anything about how it works, but I imagine tablets are wired to know when they are receiving the correct amount of input. For instance, if you connect your Streak 7 to a powered USB hub that only puts out 5 volts, it won't charge nor will it charge when connect via usb to the PC, it has to be receiving 5.5 volts and 2 amps before it will let itself receive charge. I have an iPad that is the same way and have noticed all the tablets I have had my hands on are the same, Galaxy Tabs, Transformers, Xoom... all those have to receive higher numbers to charge. So you have to have a cigarrette lighter adapter that puts that out, if it's for a cell phone it won't do anything for it
cdzo72 said:
I don't know anything about how it works, but I imagine tablets are wired to know when they are receiving the correct amount of input. For instance, if you connect your Streak 7 to a powered USB hub that only puts out 5 volts, it won't charge nor will it charge when connect via usb to the PC, it has to be receiving 5.5 volts and 2 amps before it will let itself receive charge. I have an iPad that is the same way and have noticed all the tablets I have had my hands on are the same, Galaxy Tabs, Transformers, Xoom... all those have to receive higher numbers to charge. So you have to have a cigarrette lighter adapter that puts that out, if it's for a cell phone it won't do anything for it
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The voltage is constant but current isn't. It won't know how much current is available unless it asks for it. It's like a 2A fuse, you can draw up to 2A, no more.
Even with a fully charged battery it'll show charging at 98% for a short time and that's when I saw the higher 70mA but I'm not sure if it's in the CC or CV part of a Li-Ion charge cycle but I'd guess CV because it's less than 100mA.
My bad thinking measuring AC input current instead of DC current since this thread is about USB power.
Used a cheap ReTrak USB extension cord that loses connections to seperate the wire to measure DC current. My fully charged S7 showing 100% charge still draws 150mA after hours of being plugged in. Since Li-Ion cells normally don't use a constant trickle charge, I "assume" something draws on the battery all the time along with the indicator light and buttons.
Booting up it draws a little over 1A, fully charged while booted up, it draws around 600mA. While charging and powered up, it draws 914mA. Charging while off, it draws 1160mA. Far from 2A.
wptski said:
My bad thinking measuring AC input current instead of DC current since this thread is about USB power.
Used a cheap ReTrak USB extension cord that loses connections to seperate the wire to measure DC current. My fully charged S7 showing 100% charge still draws 150mA after hours of being plugged in. Since Li-Ion cells normally don't use a constant trickle charge, I "assume" something draws on the battery all the time along with the indicator light and buttons.
Booting up it draws a little over 1A, fully charged while booted up, it draws around 600mA. While charging and powered up, it draws 914mA. Charging while off, it draws 1160mA. Far from 2A.
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I understand that, but you are missing the point, if the internal wiring of these tablets don't receive the 2A they want they WILL NOT even begin to charge. I tried literally dozens of chargers when I first got my S7, spent a couple hundred bucks actually, and none of the chargers not meant for larger devices won't work, and what those chargers all had in common, 2A output
The S7 can and will draw off low capacity ports, it just wont admit to charging unless it's at least 1A as it's just that.
I've had my S7 charge off a 500mA port on my pc at the rate of like 1%/hour while sleeping. As it's barely gaining even while idleing it's not really charging in the literal sense, but it's definitely charging in the technical sense.
Are your data lines shorted together? I believe most high draw devices wont attempt to pull 2A unless it detects that it's on a high draw charger (which I think do this to indicate it as such)
cdzo72 said:
I understand that, but you are missing the point, if the internal wiring of these tablets don't receive the 2A they want they WILL NOT even begin to charge. I tried literally dozens of chargers when I first got my S7, spent a couple hundred bucks actually, and none of the chargers not meant for larger devices won't work, and what those chargers all had in common, 2A output
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I don't know why your various chargers didn't work but it doesn't seem to be because of current. It didn't charge at 2A or even close to that.
If what your saying correct, why was I able to charge at less than 2A then? Could this be a ROM issue? I only had Froyo for a few hours but I've read that it didn't support USB charging which came with HC but it only charges with the S7 OFF.
It's possible that the demand went higher and I just didn't see on my current clamp meter. I'll have to try a current clamp and a scope to see if I missed a peak level.
Also what we are refering to as the charger might not be a charger but only a power supply and the actual charging circuit is in the S7.
I did notice one odd thing though. The green LED lights up at around 90% battery level and it's still charging. I downloaded a battery app which read the same level.
wptski said:
I don't know why your various chargers didn't work but it doesn't seem to be because of current. It didn't charge at 2A or even close to that.
If what your saying correct, why was I able to charge at less than 2A then? Could this be a ROM issue? I only had Froyo for a few hours but I've read that it didn't support USB charging which came with HC but it only charges with the S7 OFF.
It's possible that the demand went higher and I just didn't see on my current clamp meter. I'll have to try a current clamp and a scope to see if I missed a peak level.
Also what we are refering to as the charger might not be a charger but only a power supply and the actual charging circuit is in the S7.
I did notice one odd thing though. The green LED lights up at around 90% battery level and it's still charging. I downloaded a battery app which read the same level.
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You were able to charge because your charger was CAPABLE of outputting 2A at least... try charging with one that CAN'T put that out and you should find that the Streak will not charge, on ANY ROM has been my experience, custom or stock
cdzo72 said:
You were able to charge because your charger was CAPABLE of outputting 2A at least... try charging with one that CAN'T put that out and you should find that the Streak will not charge, on ANY ROM has been my experience, custom or stock
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Capable is the magic word here. The wall wart isn't putting out 2A from what I've seen, unless it does for a split second at the start which I'm going to look into.
Most wall warts at whatever their rating is put out a higher voltage with no load and slightly higher than its marked voltage under a load. If it required [email protected] max., you used a [email protected], S7 needs more current, the voltage would decrease. What's been stated here might be that the voltage was being pulled down and that's why the S7 wouldn't charge, not "really" the 2A issue.
I have a battery pack/cell load testing device used on RC stuff that connects via USB port for its graphic software. There were issues with certain Dell laptops that had a low voltage at their USB ports.
Maybe starting fully charged would help?
I have the OEM T-Mobile car charger and I've found that if I have a full charge before plugging the Streak into the charger it maintains a full charge for as long as I'm driving/using it. Otherwise, with a less than full charge I've watched it slowly discharge even though it's plugged in and is charging.
FYI: I also have a top of the line car charger for an iPad2 that charges the iPad no matter what charge level I plug it in. This iPad charger has a USB port which I have plugged the Streak USB cord into and it also doesn't keep up with the Streak's discharge if the Streak isn't a full charge to begin with. Kind of strange because I would think the iPad would draw more than a Streak. (the iPad isn't plugged in at the same time the Streak is charging)
DCoop said:
Maybe starting fully charged would help?
I have the OEM T-Mobile car charger and I've found that if I have a full charge before plugging the Streak into the charger it maintains a full charge for as long as I'm driving/using it. Otherwise, with a less than full charge I've watched it slowly discharge even though it's plugged in and is charging.
FYI: I also have a top of the line car charger for an iPad2 that charges the iPad no matter what charge level I plug it in. This iPad charger has a USB port which I have plugged the Streak USB cord into and it also doesn't keep up with the Streak's discharge if the Streak isn't a full charge to begin with. Kind of strange because I would think the iPad would draw more than a Streak. (the iPad isn't plugged in at the same time the Streak is charging)
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The S7 must run some check before it tries to charge . Whatever it is the OEM supplied power supply passes the test.
What's the specs on your two power supplies?
Just remember if you dont have the same 2A for charging in the car. You cannot charge the streak while its TURNED ON. Same with USB charging, just turn the streak OFF, then charge. It will work. =)
Otherwise, Id get a DC to AC converter for the car, plug in your normal adapter.
Background
Hi all, I, for a very short period of time was suffering from the problem of my phone DISCHARGING while it was charging. This made no logical sense to me until I did some research, which I will detail below.
How USB Power works (Roughly)
Firstly let's discuss USB power provisioning. Strictly speaking, the specifications say that any given USB port should provide a maximum of 500mA (or 0.5A) at 5 volts. *Don't shoot me electronics guys, I'm simplifying for ease of explanations sake*. Imagine that ampage as the actual force of the charger, how quickly it can ram power into your phone. Like the rate of flow on a pipe.
The beginning of the problem
This was all fine and dandy when all USB was really used for was Keyboards, Mice, Memory, etc, low current draw devices. Something else I should mention here is that the Ampage that a port CAN provide is not the Ampage it DOES provide - the device draws a certain Ampage and if the USB controller agrees it outputs said Ampage. Later, when USB was beginning to be used for more power hungry applications, ie External hard drives, these required more power than the port could (In theory) provide. However, most more modern motherboards/USB controllers were more than capable of supplying plenty more Ampage if it was requested. This was breaking the specification but not in any massively dangerous way so as such nothing bad happens.
This is where we get to the actual issue people are experiencing here. The Nexus 4 is a standards compliant device in the respect that it seems to only draw 500mA from any USB port no matter what it's potential, unless it's an AC Wall wart. If you're experiencing problems with wakelocks (see XDA) and other things, this causes your phone to draw more than 500mA which means your phone actually discharges while it's charging! Terrible!
This is quite easy to get around, but again I'm going into detail so let's explain how the phone tells the difference between a dumb wall wart and a USB controller. Easily! The USB controller obviously makes use of the data pins found within the USB cable, whereas a wallwart just (almost always) shorts them out. The Nexus 4 can detect this short, and as such draw more power *While still in quotation marks staying in spec*.
The root problem is not with how the N4 is charging, it's with the wakelock you're experiencing which is causing the phone to draw so much power while the screen is off. While the screen is off and the phone is in Deepsleep (A CPU state where it uses very little power) - it should draw no more than 50mA leaving 450mA for charging the battery, but you guys are probably experiencing a wakelock of some sort.
Solutions to the problem or How to break a specification for the good of mankind
The simple solution is to install this app: https://play.google.com/store/apps/details?id=com.rootuninstaller.batrsaver
This forces the device into a Deep sleep when the screen goes off by killing applications and turning off all internal chipsets that have wakelock capability, most commonly networking on the Nexus 4. This will allow your phone to charge (slowly) off USB without an issue. Another common wakelock is when the device is picked up by your desktop as a media device. The USB controller inside the Nexus 4 forces a wakelock which keeps it from charging. Stupid design, I know.
* A more hackish solution is to install Francos kernel, buy his app, and tick the Fast charging option in the kernel settings dialog. This will force the phone to think that everything is an AC adaptor and will force the phone to draw as much current as it can from the USB port (which on most modern motherboards is fine, and results in extremely quick charging).
* An even simpler solution than all this is to just use a 'USB Charging cable' - this is simply a cable that does not have the Data pins, and as such does exactly the same as what enabling USB fast charge above does. http://www.ebay.co.uk/itm/Micro-USB...487076?pt=PDA_Accessories&hash=item51a465d124
If you live near a Poundland store here in the UK they sell a 4 in one USB cable type thing which turns 1 USB port into Ipod sync connector, Nokia connector, MicroUSB and MiniUSB, and this doesn't have the data pins and as such is excellent.
One final point, an excellent app for monitoring whether your device is actually charging or not and how quickly is Current widget: https://play.google.com/store/apps/details?id=com.manor.currentwidget&hl=en
This widget will tell you how much Ampage is going into or leaving your battery. If the battery icon is green, then it's discharging, if it's black/white then it's charging. The bigger the number, the faster the discharge/charge. This is an extremely easy way to test speed of chargers too.
Recommendations
Another solution, just use an AC Wall wart - they're cheap as hell and the one supplied with the Nexus 4 is an extremely fast charging one. Shame I've gone and lost mine.
A way to roughly monitor charging current draw
I'd also recommend you install https://play.google.com/store/apps/details?id=com.manor.currentwidget&hl=en and monitor, if the battery is green while charging it's discharging and you need a more powerful charger/to figure out what's causing your phone to use so much power.
General good values in Current Widget
I generally saw a max draw of about 750mA for charging (not including draw for powering the device, the Nexus 4 can draw more power to charge and power the device) on my old Rev10 first generation Nexus 4. On my new Rev12 board I'm noticing this increase to about 850mA.
Are higher amperage chargers any benefit to anyone?
Yes and no. You will not notice faster charging unless you use your device while charging. Your nexus will draw as much power as it needs to power the phone while charging at the fastest rate. For example on the stock 1.2a charger
1200mA | 800mA goes to charging 400mA goes to powering the phone idling
Let's say you start a stability test. Your phone will obviously be using a lot more power so this will happen
1200mA | -600mA goes to charging and 1800mA goes to powering the phone stability testing
That minus value above may look strange! Let me explain. If the phone needs more power than the charger can supply, it will draw from the battery. That's the minus number.
If you have a higher ampage charger like for example a 2.5a charger
2500mA | 800mA goes to charging 400mA goes to powering the device
Stability testing
2500mA | 700mA goes to charging 1800mA goes to powering the device
Can you see the difference?
DISCLAIMER: I am not an electronics engineer nor do I claim to be, I am simply a hobbyist and this is what I've found to be the case. Please correct me if I've made any mistakes, I want to learn.
Thanks!
Thanks so much for this post. It's very helpful.
kn100 said:
Another common wakelock is when the device is picked up by your desktop as a media device. The USB controller inside the Nexus 4 forces a wakelock which keeps it from charging. Stupid design, I know.
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This isn't true for everyone then as mine connects and charges just fine off of my laptop and desktop when connected as a media device. In fact its on my laptop right now charging, gone from 68% to 81% in about 30 minutes and it shows connected as a portable media player.
Great info! Thanks for writing this!
In certain use cases the Nexus4 discharges faster than it charges and this is a very useful guide.
I use my phone for navigation in my car and having the GPS on and the screen at high brightness
drains the battery faster than the 0.5A car chargers can supply. Car chargers rated for 2.0A work well.
I haven't tried a 'USB charging cable' with the data pins shorted, it may work as well.
-Mindroid- said:
Great info! Thanks for writing this!
In certain use cases the Nexus4 discharges faster than it charges and this is a very useful guide.
I use my phone for navigation in my car and having the GPS on and the screen at high brightness
drains the battery faster than the 0.5A car chargers can supply. Car chargers rated for 2.0A work well.
I haven't tried a 'USB charging cable' with the data pins shorted, it may work as well.
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was over in Nexus 7 forums and the 4.2.x kernel should have solved the problem at least for having to use shorted cables. have to wait and see if 4.2.2 brings any more changes.
http://forum.xda-developers.com/showthread.php?t=1984838
Section 6 in this link is about power supplied through USB
http://en.wikipedia.org/wiki/Universal_Serial_Bus
I can't tell if we have an updated kernel allowing faster usb charging as I'm limited by the power output of the usb port in my laptop. The output (5V at 500mA max) is controlled by the laptop (USB Standards) and it doesn't matter what the phone or cable is capable of as that's the max it will give out and that's about what I'm charging at. If I had a dedicated charging port in my laptop then it would be different and I could see if its able to draw more power. I have a 1.0 amp port in my car and it does charge at the higher amperage, I would assume it would do the same thing if I had a 2 amp usb port in the car. So I think the stock kernel has the fast usb charge built in it just depends upon if you have a usb port capable of providing a faster charger, it has nothing to do with the cable as I'm using a standard unmodified micro usb cable and its able to draw the max a usb device is able to put out.
thanks
thanks for a great detailed post!!!
I have the same trouble with my N4 when I was charging while using my phone...
I find it very slow... I guess I've been spoiled by my previous iPhone (which charges fairly fast)....
i might be stating the obvious but I find the phone charged "a lot" faster when it's OFF
if you are running low with your battery and need a quick 10 min charge, just do yourself a favour by turning off your phone...
the difference is quite significant!
kzoodroid said:
This isn't true for everyone then as mine connects and charges just fine off of my laptop and desktop when connected as a media device. In fact its on my laptop right now charging, gone from 68% to 81% in about 30 minutes and it shows connected as a portable media player.
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Yup, me too. It only discharges while charging when I am playing like NFS most wanted.
Sent from my Nexus 4 using xda app-developers app
The issue with cables is with the LG usb wall charger as the one supplied isn't capable of getting the 5 volts at 1.2 amps that the charger is rated at, mine is getting around 300 - 400 mA. The micro usb cable I have in my car and use with my laptop (for charging and data transfer) is able to handle the higher amperage, it gets around 1 amp with the LG plug. There are no specs on these cables so I can't list a definitive difference and I would assume that the cable mod in the OP might help with the LG cable. It also might just be simpler to only buy those cables capable of handling higher amperage as obviously they are out there from my experience.
The cable I'm using is an RCA coiled charging/syncing cable model AH732CBR (has data pins). The maximum I'm getting from this is about 870 mA regardless of the amperage of the usb port, I've tried a 1.0, 1.2 and 2.1 and they are all around 870 mA on current widget. I would suppose if I could find a strictly charging cable I could get higher (link to ebay in OP is outdated) but this is still 2x that which I'm getting from the LG cable supplied with the phone which only puts out 300-400 mA. Our phone also has Qualcomm's quick charge which is supposed to improve battery charging times by 40%.
http://www.droid-life.com/2013/02/1...allows-your-device-to-charge-up-to-40-faster/
How do you measure how much mA the device draw from the charger?
Sent from my Nexus 4 using Tapatalk 2
omrij said:
How do you measure how much mA the device draw from the charger?
Sent from my Nexus 4 using Tapatalk 2
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current widget, link is in the OP
kzoodroid said:
The cable I'm using is an RCA coiled charging/syncing cable model AH732CBR (has data pins). The maximum I'm getting from this is about 870 mA regardless of the amperage of the usb port, I've tried a 1.0, 1.2 and 2.1 and they are all around 870 mA on current widget. I would suppose if I could find a strictly charging cable I could get higher (link to ebay in OP is outdated) but this is still 2x that which I'm getting from the LG cable supplied with the phone which only puts out 300-400 mA. Our phone also has Qualcomm's quick charge which is supposed to improve battery charging times by 40%.
http://www.droid-life.com/2013/02/1...allows-your-device-to-charge-up-to-40-faster/
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Bit of a late reply but please bear in mind the Nexus will NOT draw anything more than about 800mAh from the wall for charging alone. That is the absolute max and is a hardware limit - If the cable is transmitting that and it's showing in current widget you've got a good setup. See the added section in OP for more info on higher amperage chargers.
It only shows up as a USB connection for media instead of charging. Is there anything I have to change on my N6 settings? My old iPhone charged fine.
Maybe it requires a higher ampere charger?
lude219 said:
Maybe it requires a higher ampere charger?
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How do I find out?
dinosaur1 said:
It only shows up as a USB connection for media instead of charging. Is there anything I have to change on my N6 settings? My old iPhone charged fine.
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I have never had an Android phone that would charge from car's USB. Never knew whether it was the phone or the car. I can play music from USB thumb drives or some phones through the car's USB port. Always have to use the 12v charger. If your i Phone did, you might see if a "Charge Only " cable would work. That cable is a good thing to have, regardless.
wtherrell said:
I have never had an Android phone that would charge from car's USB. Never knew whether it was the phone or the car. I can play music from USB thumb drives or some phones through the car's USB port. Always have to use the 12v charger. If your i Phone did, you might see if a "Charge Only " cable would work. That cable is a good thing to have, regardless.
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Can you send a link ? I wouldn't mind buying one.
All android phones determine whether a charger is a wall charger or a computer by whether or not the two center USB pins are shorted. If they are, then it's a wall charger, and will show "Charging (AC)" in the battery screen. Wall chargers designed for iOS devices work differently, and as such most of them will only charge Android devices at 500mA, which is the the same as a computer's USB ports, regardless of the marked amperage. In other words, a 2A charger designed for iOS will still charge Android devices at 500mA.
"Charge Only" cables are also an issue. Many of them don't actually have center pins at all. Android considers this an "open." In a "short," the resistance is zero Ohms. In an "open," the resistance is infinity Ohms. (Infinity, being the exact opposite of zero.) So, a lot of charge only cables will cause your android device to charge at 500mA.
The solution is to ensure that your charger is designed for Android. Or, buy a charge only cable designed for android. Or, buy an adapter that turns any cable into a charge only cable designed for android.
Yes, I know that's all really confusing. Here's the real deal. Find a charger and cable that works for sure (oh, I don't know... like, the one that came with the device!). Plug it in, and go to the battery screen. Ensure it says "Charging (AC)". Once that's a given, replace the cable with any other cable that you want to use. If it still says "Charging (AC)," then it's a good charging cable. If it says "Charging (USB)," then it's not a good charging cable. If you ever plug a known good charging cable into a charger, and get the dreaded "Charging (USB)," then you know your charger isn't Android compatible, making it a bad charger.
So, the TL;DR of it all: Use the original charger to test cables. Use the cables that pass that test to test chargers. Other than that, it's a crapshoot.
jt3 said:
All android phones determine whether a charger is a wall charger or a computer by whether or not the two center USB pins are shorted. If they are, then it's a wall charger, and will show "Charging (AC)" in the battery screen. Wall chargers designed for iOS devices work differently, and as such most of them will only charge Android devices at 500mA, which is the the same as a computer's USB ports, regardless of the marked amperage. In other words, a 2A charger designed for iOS will still charge Android devices at 500mA.
"Charge Only" cables are also an issue. Many of them don't actually have center pins at all. Android considers this an "open." In a "short," the resistance is zero Ohms. In an "open," the resistance is infinity Ohms. (Infinity, being the exact opposite of zero.) So, a lot of charge only cables will cause your android device to charge at 500mA.
The solution is to ensure that your charger is designed for Android. Or, buy a charge only cable designed for android. Or, buy an adapter that turns any cable into a charge only cable designed for android.
Yes, I know that's all really confusing. Here's the real deal. Find a charger and cable that works for sure (oh, I don't know... like, the one that came with the device!). Plug it in, and go to the battery screen. Ensure it says "Charging (AC)". Once that's a given, replace the cable with any other cable that you want to use. If it still says "Charging (AC)," then it's a good charging cable. If it says "Charging (USB)," then it's not a good charging cable. If you ever plug a known good charging cable into a charger, and get the dreaded "Charging (USB)," then you know your charger isn't Android compatible, making it a bad charger.
So, the TL;DR of it all: Use the original charger to test cables. Use the cables that pass that test to test chargers. Other than that, it's a crapshoot.
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Yes I'm using the cable that came with my N6 to plug it into the built in USB port. I have a 2014 4Runner with the Entune system.
dinosaur1 said:
Yes I'm using the cable that came with my N6 to plug it into the built in USB port. I have a 2014 4Runner with the Entune system.
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Most "built in" car USB ports are 500mA, so will show as USB chargers (not AC chargers). Those that are higher (1A or 2A), tend to be designed for iOS devices (so will STILL show as USB chargers, unless you get a cable or adapter that has the two center pins shorted). I've yet to see a built-in car USB slot that will charge an Android device in AC mode.
jt3 said:
Most "built in" car USB ports are 500mA, so will show as USB chargers. Those that are higher, tend to be designed for iOS devices. I've yet to see a built-in car USB slot that will charge an Android device in AC mode.
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That's what I thought. Could you recommend what charger I could use to plug in to using the cable that came with the N6?
dinosaur1 said:
That's what I thought. Could you recommend what charger I could use to plug in to using the cable that came with the N6?
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That's a very hard question to answer. Chargers tend to advertise iOS compatibility, but do NOT tend to advertise Android compatibility. However, they often do advertise a specific android device. So, for example, you might find a car charger that advertises compatibility with the Samsung S5. As long as it's advertising compatibility with any Android device, it should work with YOUR Android device. Just be aware that most manufacturers don't understand the whole AC vs USB thing, so even if they advertise compatibility, it's not ensured. Just be sure to buy chargers where you can take them back for a refund if they end up not showing up as working in AC mode for your device.
jt3 said:
That's a very hard question to answer. Chargers tend to advertise iOS compatibility, but do NOT tend to advertise Android compatibility. However, they often do advertise a specific android device. So, for example, you might find a car charger that advertises compatibility with the Samsung S5. As long as it's advertising compatibility with any Android device, it should work with YOUR Android device. Just be aware that most manufacturers don't understand the whole AC vs USB thing, so even if they advertise compatibility, it's not ensured. Just be sure to buy chargers where you can take them back for a refund if they end up not working.
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Sounds like I need to search for chargers for my N6 to plug in my 12v.
Someone just posted this in another thread. It's a car charger that supposedly supports Qualcomm Quick Charge 2.0, so it'd be the equivalent of the Moto Turbo Charger for a car. http://www.amazon.com/dp/B00P9UILUM/ref=cm_sw_r_udp_awd_0fvAub0VPYE9B
Since that's an Android thing, it'd almost be certain to work for all Android devices.
jt3 said:
Someone just posted this in another thread. It's a car charger that supposedly supports Qualcomm Quick Charge 2.0, so it'd be the equivalent of the Moto Turbo Charger for a car. http://www.amazon.com/dp/B00P9UILUM/ref=cm_sw_r_udp_awd_0fvAub0VPYE9B
Since that's an Android thing, it'd almost be certain to work for all Android devices.
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Should I even attempt to try an adapter first?
dinosaur1 said:
Should I even attempt to try an adapter first?
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Normally, I'd say yes, but in this case, since you have an N6, nothing is going to compare to having a Qualcomm Quick Charge 2.0 compatible charger.
jt3 said:
Normally, I'd say yes, but in this case, since you have an N6, nothing is going to compare to having a Qualcomm Quick Charge 2.0 compatible charger.
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Thanks. I'll definitely have to buy one asap.
jt3 said:
Normally, I'd say yes, but in this case, since you have an N6, nothing is going to compare to having a Qualcomm Quick Charge 2.0 compatible charger.
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Stay away from a charge only cable as well?
dinosaur1 said:
Stay away from a charge only cable as well?
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Another hard question. There are two types of "charge only" cables. One that has the middle two (data) pins shorted together, and one where they're just missing (even though the pins themselves may be there... they're not connected). The former would work fine. The latter wouldn't (or more specifically, it would work, but only show up as "Charging (USB)" in the battery monitor).
Determining which is which before purchase is virtually impossible. The only way to really tell is to try it with a known good (1A or higher) charger.
jt3 said:
Another hard question. There are two types of "charge only" cables. One that has the middle two (data) pins shorted, and one where they're just missing (even though the pins themselves may be there... they're not connected). The former would work fine. The latter wouldn't (or more specifically, they'd work, but only show up as "Charging (USB)" in the battery monitor).
Determining which is which before purchase is virtually impossible. The only way to really tell is to try it with a known good (1A or higher) charger.
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I'll stick with the Qualcomm car charger. By the way can it harm the phones battery over time if I constantly use the turbo charger at home and at work and the turbo charger in my car?
dinosaur1 said:
I'll stick with the Qualcomm car charger. By the way can it harm the phones battery over time if I constantly use the turbo charger at home and at work and the turbo charger in my car?
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Nope. They're designed to use that type of charger. Technically, rapid charging may decrease battery life, but you'll probably long since have moved on to a new phone by the time you'd have to worry about that. The only caveat is that you should NEVER start your car while the phone is plugged in (on ANY car charger). When you're starting your car, the 12V electrical system in your car can experience quite a large power surge, and that can transmit through the adapter and hurt your phone. The electrical system in your car is built to withstand that. Your phone isn't. Most (quality) car chargers will have a similar warning somewhere, since it's a pretty standard warning.
jt3 said:
Nope. They're designed to use that type of charger. Technically, rapid charging may decrease battery life, but you'll probably long since have moved on to a new phone by the time you'd have to worry about that. The only caveat is that you should NEVER start your car while the phone is plugged in (on ANY car charger). When you're starting your car, the 12V electrical system in your car can experience quite a large power surge, and that can transmit through the adapter and hurt your phone. The electrical system in your car is built to withstand that. Your phone isn't. Most (quality) car chargers will have a similar warning somewhere, since it's a pretty standard warning.
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Personally would you go with the charger you listed above? Amazon also lists USB cables that my N6 came with which is model skn5004a. Should I stick with that type of USB cables for extra cables I carry while traveling, work and auto?