Background: (feel free to skip this)
In my search to get a good car charger for my Nexus 10 (that would also be good on my Galaxy Nexus), I checked out a bunch of sites and manufacturers and reviews for the perfect charger. I also wanted it to be dual port for two phones at the same time in case my girlfriend is in the car.
So many 2A chargers are not actually 2A, they may be 1A to each port max or they may only work as 2A on an iPad. Android devices look for shorted out data connections in order to pull more than USB power (500ma). So a charger has to both offer 2A or more and have the data pins shorted in order for us to get maximum current to our Nexus 10's. The Apple/iPad chargers work differently. They either have smart chips or specific resistances between the data pins in order to specify current draw.
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What you came here for:
After the long search, the BEST while still very affordable car adapter, is the *drumroll*:
Bracketron Universal Dual USB Car Adapter
2 ports like I wanted. 2A like I wanted.
Contrary to the "Universal" listing, the adapter was likely made for the iPad. So charging out of the box is USB (500ma). But it's easily fixed in under 3 minutes!
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Instructions:
1. Pop off the round silver plate on the front (with your finger/nail).
2. Unscrew the silver part in the back. Don't lose the spring hidden inside.
3. Slowly pry open the black plastic. It's fairly rigid and you'll hear some clicks. If you don't open it like a crazy monkey, you won't damage or break any plastic.
4. You'll see by each USB port 4 wires going to the port from the circuit board. The 2 middle pins are the data lines, the 2 outer ones are the power lines.
5***. You want to short the data (two middle) pins. All that means is you want them touching electrically. Takes about 10 seconds to do with a solder iron (once it's hot ). Just flow some solder between the two pins, no wire needed. Do the same for the other USB port on the other side.
6. Put the plastic and screwed pieces back together. Plug it in and you should see AC charging! :victory:
***If you're poor at soldering, don't worry - you're doing this on pins in the air, not directly on the board, so it's an extremely easy soldering job. If you've never soldered in your life, you can possibly use some wire instead of solder to connect the two and find a way for it to hold in place. But seriously it's an easy solder job and you should probably learn how to solder anyway.
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Reading the instructions I wrote takes longer than making the modification.
Why this adapter if you have to solder? It's the only one I can find with dual ports that can actually give 2A to an ANDROID device. Why this of all the other adapters you can attempt to solder? It comes apart extremely easily so you don't break any plastic like many of the other ones. And the adapter is really small so you don't have a huge piece of plastic hanging out of your power port.
Fair note: it looks like it may give 2A max, so charging both my 1A phone and my 2A tablet will actually be slower. But it's perfect for charging the tablet at full speed when by itself or two phones at full speed.
Also, credit to Amazon reviewer 'K. Crawford' for suggesting this adapter as a good one to mod.
If anyone needs help during the process, I'm more than happy to help!
Very nice info, thanks.
Niiice! I heard though even if you hook up the tablet to a 2A charger, the tab will still only take a reduced amount, is that true?
From my measurements, the tablet will draw around 750 ma, so soldering it will help, just not for the full 2A.
rp181 said:
From my measurements, the tablet will draw around 750 ma, so soldering it will help, just not for the full 2A.
Click to expand...
Click to collapse
You measured 750 ma with the bracketron I linked post-mod?? It should be much higher.. What did you use to measure?
nice instructions, royal.
did I do it right?! check the details beneath one of the photos. you will see some solder popped and landed on the circuit board on the top right. it is touching one of those little enclosed boxes on its own and nothing else. you think this is gonna pose a problem?! if so, any fix? I tried to pull it away, but im not a mastersolderer.
bummer about the picture rule. I think I got some good shots that could help some people. I guess I'll be back to post the pics.
This charger is dearer but supplies dual 2.1A with the correct cables/
http://www.expansys-usa.com/expansys-expansys-dual-car-charger-adapter-5v-4-2a-219640/
Gaugerer said:
This charger is dearer but supplies dual 2.1A with the correct cables/
http://www.expansys-usa.com/expansys-expansys-dual-car-charger-adapter-5v-4-2a-219640/
Click to expand...
Click to collapse
It doesn't state if it's "shared" or not. Meaning is that 2.1A total for both or 2.1A each. Lot of them are shared even at 3.1A.
wptski said:
It doesn't state if it's "shared" or not. Meaning is that 2.1A total for both or 2.1A each. Lot of them are shared even at 3.1A.
Click to expand...
Click to collapse
It says 5v, 4.2A so that is 2.1A each.
Gaugerer said:
It says 5v, 4.2A so that is 2.1A each.
Click to expand...
Click to collapse
Ah! My bad, I see that at the top now!
slippy steve said:
nice instructions, royal.
bummer about the picture rule. I think I got some good shots that could help some people. I guess I'll be back to post the pics.
Click to expand...
Click to collapse
Are you able to post pictures yet? I'm happy to take a look and help out. If it won't let you attach pictures, you can try linking to an album on imgur, for example (if it allows links).
Gaugerer said:
This charger is dearer but supplies dual 2.1A with the correct cables/
http://www.expansys-usa.com/expansys-expansys-dual-car-charger-adapter-5v-4-2a-219640/
Click to expand...
Click to collapse
With the iPad designation, it's a sure thing that this will need modification. If I'm understanding you correctly, I think you're trying to suggest modified (data-shorted) cables rather than modified adapter. I prefer having a modified adapter so I can use and replace cables at a whim. But if you purchased that one already, you can see if it comes apart and can be modified just as easily.
Royal2000H said:
Are you able to post pictures yet? I'm happy to take a look and help out. If it won't let you attach pictures, you can try linking to an album on imgur, for example (if it allows links).
With the iPad designation, it's a sure thing that this will need modification. If I'm understanding you correctly, I think you're trying to suggest modified (data-shorted) cables rather than modified adapter. I prefer having a modified adapter so I can use and replace cables at a whim. But if you purchased that one already, you can see if it comes apart and can be modified just as easily.
Click to expand...
Click to collapse
I purchased a Kensington car charger packaged for an iPad and all that meant is that it came a iPad type cord but still a standard USB port which worked on my Android device.
Some people have said that the cable used also has a lot to do with what the tablet pulls. Some saying a Motorola brand USB cable they had gave much more current. If there is any truth to this then in conjunction with doing this mod to the charger it might be a good idea to buy a cable with 22AWG power conductors:
http://www.newegg.com/Product/Product.aspx?Item=N82E16812189234
wptski said:
I purchased a Kensington car charger packaged for an iPad and all that meant is that it came a iPad type cord but still a standard USB port which worked on my Android device.
Click to expand...
Click to collapse
The question isn't whether the port is USB. It's always going to be USB supplying 5V. The question is how much current the device can pull from the charger. A normal USB port (like a computer) can only supply 500mA by spec. The N10 needs 2A. The ones designated for ipad will usually charge your N10 but at a max of 500mA (even if they're rated higher - because the data pins aren't shorted).
Royal2000H said:
The question isn't whether the port is USB. It's always going to be USB supplying 5V. The question is how much current the device can pull from the charger. A normal USB port (like a computer) can only supply 500mA by spec. The N10 needs 2A. The ones designated for ipad will usually charge your N10 but at a max of 500mA (even if they're rated higher - because the data pins aren't shorted).
Click to expand...
Click to collapse
If the data pins aren't shorted, it won't draw more than 500ma, if that's so, how can it be rated at 2.A? I haven't tried my PS with the Nexus 10 yet but did with my other device, had no problem but it has a much smaller battery and I don't remember the details.
I'll try to check it out on the Nexus 10 and post the results.
EDIT
I thried my Kensington or this one: http://www.amazon.com/Kindle-PowerB...158903&sr=1-7&keywords=kensington+car+charger.
I first tried it using a POGO cord and it wouldn't charge. It did using a micro-USB cord over 500ma also.
wptski said:
If the data pins aren't shorted, it won't draw more than 500ma, if that's so, how can it be rated at 2.A? I haven't tried my PS with the Nexus 10 yet but did with my other device, had no problem but it has a much smaller battery and I don't remember the details.
I'll try to check it out on the Nexus 10 and post the results.
EDIT
I thried my Kensington or this one: http://www.amazon.com/Kindle-PowerB...158903&sr=1-7&keywords=kensington+car+charger.
I first tried it using a POGO cord and it wouldn't charge. It did using a micro-USB cord over 500ma also.
Click to expand...
Click to collapse
I explained it all in the Original Post, but I'll try to clarify. If a charger is rated at 2A but doesn't have data pins shorted, the Nexus 10 will only pull 500mA. The manufacturer isn't necessarily lying about the 2A, it likely is capable of giving 2A. However, the Nexus 10 checks for shorted pins before pulling at 2A. This is because USB spec is rated for 500mA and if the Nexus 10 tried to pull 2A from a computer, it would overload the circuits of a computer's USB port and potentially damage the USB hub or computer. So as a somewhat universal decision (though really it's not standardized), most manufacturers did something like this: if data pins are not shorted (as in a computer) - take upto 500mA. If data pins are shorted (as in the charger provided with the device) - take upto what's necessary. This is actually a somewhat problematic solution because a 2A-requiring Nexus 10 plugged into, say, a Galaxy Nexus charger (shorted data but only 1A) could potentially cause damage from overloading.
Therefore, Apple didn't go along with the whole shorting the data pins solution. They came up with their own solution, which I actually don't know enough about to speak of in accuracy. But their solution allows the device to basically "sense" the capabilities of a charger, so it knows whether it can charge 1A or 2A or 3A, etc. This is I imagine is either done with resistors specifying discrete values or with some sort of "smart chips".
So, as you see, the Apple ones don't have shorted data pins. Therefore a manufacturer of a car charger has to decide: Support Apple devices or support other devices? And some manufacturers do such a bad job, they provide the high current (like 2A) but then don't do Apple's "solution" or the data shorting, thereby rendering their high current useless.
Royal2000H said:
I explained it all in the Original Post, but I'll try to clarify. If a charger is rated at 2A but doesn't have data pins shorted, the Nexus 10 will only pull 500mA. The manufacturer isn't necessarily lying about the 2A, it likely is capable of giving 2A. However, the Nexus 10 checks for shorted pins before pulling at 2A. This is because USB spec is rated for 500mA and if the Nexus 10 tried to pull 2A from a computer, it would overload the circuits of a computer's USB port and potentially damage the USB hub or computer. So as a somewhat universal decision (though really it's not standardized), most manufacturers did something like this: if data pins are not shorted (as in a computer) - take upto 500mA. If data pins are shorted (as in the charger provided with the device) - take upto what's necessary. This is actually a somewhat problematic solution because a 2A-requiring Nexus 10 plugged into, say, a Galaxy Nexus charger (shorted data but only 1A) could potentially cause damage from overloading.
Therefore, Apple didn't go along with the whole shorting the data pins solution. They came up with their own solution, which I actually don't know enough about to speak of in accuracy. But their solution allows the device to basically "sense" the capabilities of a charger, so it knows whether it can charge 1A or 2A or 3A, etc. This is I imagine is either done with resistors specifying discrete values or with some sort of "smart chips".
So, as you see, the Apple ones don't have shorted data pins. Therefore a manufacturer of a car charger has to decide: Support Apple devices or support other devices? And some manufacturers do such a bad job, they provide the high current (like 2A) but then don't do Apple's "solution" or the data shorting, thereby rendering their high current useless.
Click to expand...
Click to collapse
If you were to use a PS limited to 1A, it "should" have a saftey to limit that. I used my above mentioned 2.1A PS with a 110VAC>12VDC adapter which was has a 1A max. and it did limit the output. Not saying that all PS would do that without damage though.
While poking around in files, I did find one that lists the power source by name but I forget as to what it showed for the OEM PS. I wonder what it'll show for a car PS?
Sv: Best 2A car charger: Bracketron
I doubt there are phone chargers without current limitations as safety feature. If designed well the charger should limit the current at its max current. Otherwise a lot of chargers would burn.
But I am not sure this is the reality
Skickat från min HTC Desire via Tapatalk 2
Royal2000H said:
...Apple didn't go along with the whole shorting the data pins solution. They came up with their own solution, which I actually don't know enough about to speak of in accuracy. But their solution allows the device to basically "sense" the capabilities of a charger, so it knows whether it can charge 1A or 2A or 3A, etc. This is I imagine is either done with resistors specifying discrete values or with some sort of "smart chips".
Click to expand...
Click to collapse
I believe Apple use a pair of different value resistors to create a voltage divider, passing a different voltage to D+ and D-. The presence of this differential voltage on the data pins is what triggers the high power charge capabilities.
Related
Hi,
I just stuck here, cause I found a thread about fast usb charging. But there is no answers or solutions.
I have many htc devices. It seems that some of them has a problem with 3rd party usb chargers.
My most used device is Universal. It suck a lot of power. THis one doesn't enable usb charging at all, until you put it in sleep mode before pluging the charger.
Anyway, the same issue for Kaiser too.
The problem is, that it doesn't matter how much current is the charger able to deliver. They just use some kind of recognition of original chargers.
What I already measured: Original charger and universal running => takes 1200mA. 3rd party charger or my 5A PSU => Universal/Kaiser sucks just 500mA.
This is fast/slow charge. I found here discussion about 4 and 5 pins shorted??
But WTF which 4 & 5 pin?
http://www.tracyandmatt.co.uk/blogs/index.php/2006/09/10/htc_hermes_usb_connector_pin_config
According to this pinout. It would be 2 GND of Audio side? I'm not sure that original charger use extUSB audio side to charge...? It also could be D & A pins, but I'm afraid to connect 5V to Data- pin.
Anyway, someone here have to know it.
If not, in a few days I'll try all possible combinations and post the results.
Thanks
Shef
I'd also be interested to know about this. When I charge my TYTN II via USB, it takes much longer to charge than if I charge it via the mains charger (I prefer USB since I travel a lot and it's one less charger I need to carry around).
Better still, is it possible to buy a USB cable that will charge at the same rate as the mains charger rather than messing with a USB cable with the associated risks?
Best,
Gary.
Shef said:
Hi,
What I already measured: Original charger and universal running => takes 1200mA. 3rd party charger or my 5A PSU => Universal/Kaiser sucks just 500mA.
This is fast/slow charge. I found here discussion about 4 and 5 pins shorted??
But WTF which 4 & 5 pin?
http://www.tracyandmatt.co.uk/blogs/index.php/2006/09/10/htc_hermes_usb_connector_pin_config
Click to expand...
Click to collapse
a usb port only supplies 500ma, while the wall charger does 1200ma as the OP has measured (although it says 1A at the back of the charger). changing a cable is not gonna superpower up your usb port.
unless maybe you get hold of a forked USB cable, like the one that Seagate Free Agent drives come supplied with... you know, 1 mini USB splitting halfway down to two normal USB plugs.
Worth experimenting with, do you think?
wyrm said:
unless maybe you get hold of a forked USB cable, like the one that Seagate Free Agent drives come supplied with... you know, 1 mini USB splitting halfway down to two normal USB plugs.
Worth experimenting with, do you think?
Click to expand...
Click to collapse
good call.......with a little googling i came up with this
http://www.universaluk.com/acatalog...2_x_Type_A_to_mini_B__USB_2_0__1m__Lindy.html
tried ebay, my brief search came up with lots of unrelated results, so i gave up
I got one of those leads, came with my portable 2.5" hard drive. Just tried the lead on my Tytn 2 and it does charge almost as fast as the mains plug
Success
Ok, so, I tried to experiment.
Here you go.
Usb simple cable 480ma charge.
The same result with Motorola charger.
Motorola charger pins A and B short circuit - 890mA.
That's much better, althrough I suppose it can suck more current then 890mA, but it's significantly better.
THere is also pins data+ and data- short circuited (I don't know if it has effect, but I can't disconnect it in this connector).
Apparently NC (not connected) pin on our pinout schematics definitely is connected.
With % of charged battery it suck less and less current....I suppose it's usual, this should be even driven by ROM.
So, update your cables
It works even with car charger, so no more charger problems...
Shef
Just to be clear - you took a Motorola USB cable and shorted pins A and B (which are which by the way?) and it provides a decent current....
How do you short the pins? I've looked in the end of cable and I can hardly see the pins, let alone short them! What's the trick here or have I missed something?
Thanks,
Gary.
Shef said:
Ok, so, I tried to experiment.
Here you go.
Usb simple cable 480ma charge.
The same result with Motorola charger.
Motorola charger pins A and B short circuit - 890mA.
That's much better, althrough I suppose it can suck more current then 890mA, but it's significantly better.
THere is also pins data+ and data- short circuited (I don't know if it has effect, but I can't disconnect it in this connector).
Apparently NC (not connected) pin on our pinout schematics definitely is connected.
With % of charged battery it suck less and less current....I suppose it's usual, this should be even driven by ROM.
So, update your cables
It works even with car charger, so no more charger problems...
Shef
Click to expand...
Click to collapse
Also interested in how to short the pins. I use Navizon, bluetooth HSDPA tethering, and iGuidance while on the ambulance and even my iGo 3A max rated charger can barely keep up because the tilt wont accept all of the available current.
So have anyone found a way to fast charge our ppc through usb??
Yes, that is correct. Short pins 4 & 5 (4 is normally NC) to enable fast-charging. If you do it correctly, the phone shouldn't pick up tethering, and therefore should not say "PC Connected" or the like..
The TracyAndMatt pinout is wrongly numbered. The pin assignments are correct, but the number/letter scheme they used is incorrect. True ExtUSB pinout translation to their pinout is as follows:
T & M Real ExtUSB
-------------------------------
Pins E D C B A = 1 2 3 4 5
Pins 1 2 3 4 5 6 = 6 7 8 9 10 11
The way I remember is that the corner opposite the angled one is where pin 1 starts (where E is on the T&M pinout) - and they go like most IEC-standard connectors, in a clock-like circular numbering scheme.
Here's a better pinout: http://pinouts.ru/PDA/htc_extUSB_pinout.shtml
Hope this helps!
--W5i2
its the milliamps that is the problem even doubling up with a y splitter does not do much Find a charger with the most milliamps for a faster charge 1.2 amps works best and as far as i know no usb port puts out that much even if they are wired in a series. Many try to sell lower amp chargers they dont even know about it at att. if the screen is off they will charge but not well these phones are energy hogs. I must have at least twenty chargers and messed around with them... the original or one of highest amperage works for me.
Check winhlp.com/node/855 for the answer.
htc_battery_trout.c said:
/* A9 reports USB charging when helf AC cable in and China AC charger. */
/* Work arround: notify userspace AC charging first,
and notify USB charging again when receiving usb connected notificaiton from usb driver. *
Click to expand...
Click to collapse
I find this annoying. I can't tell if my wall charger is fast charging or not because the G1 always says "AC"
hgmichna said:
Check winhlp.com/node/855 for the answer.
Click to expand...
Click to collapse
That is not going to help HTC owners.
HTC charging cable
kiss_se said:
That is not going to help HTC owners.
Click to expand...
Click to collapse
http://winhlp.com/node/855 was explicitly written for HTC smartphone owners.
hgmichna said:
[...] was explicitly written for HTC smartphone owners.
Click to expand...
Click to collapse
Sorry, I meant to say: That is not going to help extusb owners.
hgmichna said:
Check winhlp.com/node/855 for the answer.
Click to expand...
Click to collapse
Is it possible to get one of the 'fast charge' enabled USB cables on eBay or elsewhere? I am not keen on doing the mod described.
What is the maximum mAh recommended for HTC devices? Is it still 1.2 A or more?
zurpher said:
Is it possible to get one of the 'fast charge' enabled USB cables on eBay or elsewhere? I am not keen on doing the mod described.
Click to expand...
Click to collapse
Check http://winhlp.com/node/855#qaes for the only buyable solution I know, besides compatible chargers. Your best bet is probably the original HTC charger, available for roughly $10.
zurpher said:
What is the maximum mAh recommended for HTC devices? Is it still 1.2 A or more?
Click to expand...
Click to collapse
There can be no recommended maximum mAh. There can only be a required current, which differs from device to device. Check Ohm's Law. The device determines how much current it draws. If the charger cannot deliver that current, then the charging process can fail in various ways, all undesirable.
hgmichna said:
Check http://winhlp.com/node/855#qaes for the only buyable solution I know, besides compatible chargers. Your best bet is probably the original HTC charger, available for roughly $10.
There can be no recommended maximum mAh. There can only be a required current, which differs from device to device. Check Ohm's Law. The device determines how much current it draws. If the charger cannot deliver that current, then the charging process can fail in various ways, all undesirable.
Click to expand...
Click to collapse
Could the USB Switching 2A Power Charger Adapter Convertor Plug be similar in function to the one that you've linked?
zurpher said:
Could the USB Switching 2A Power Charger Adapter Convertor Plug be similar in function to the one that you've linked?
Click to expand...
Click to collapse
I don't know, but probably not. Apple used to use a different signalling scheme involving resistors.
I bought a couple of these several months ago from DealExtreme.com to use for other USB powered devices.
http://www.dealextreme.com/p/usb-re...emergency-power-with-cell-phones-holder-44749
For kicks and giggles, I was curious how much current the things really put out. I connected to my CM7 NC with the NC USB cable and did a dmesg | grep CHARGER
To my surprise, even though DealExtreme claims that these output 1A, the NC said it was receiving 2A! (see attached photo of screen).
When I used a standard Micro-USB cable, the current dropped down to 500mA.
I haven't yet done any sort of extensive testing to see what kind of life I get out of these. If the other specs are correct (a little dubious now), then having 2 of these, fully charged, would be like having an extra internal battery. Not bad for less than $13 ea.
Anyone know how accurate (or inaccurate) the output from the dmesg command is? Is the Nook misrepresenting what it says it's getting from the charger?
I suspect that what you're seeing on the screenshot is not the charging current but that it recognizes the plug type (B&N 2amp) or standard USB (500ma) that is actually plugged in. Nevertheless it still could be a handy gizmo to have around.
___________________
- Derek
derekr said:
I suspect that what you're seeing on the screenshot is not the charging current but that it recognizes the plug type (B&N 2amp) or standard USB (500ma) that is actually plugged in. Nevertheless it still could be a handy gizmo to have around.
___________________
- Derek
Click to expand...
Click to collapse
When I used a different model of External USB battery with the same B&N NC cable, it registered as 500mA, exactly as that particular model is rated. Though your thought is justifiably skeptical (and I'm an unrepentant skeptic myself), further evidence suggests there's more going on than just detecting the additonal pins in the B&N NC cable.
Jgrimoldy said:
When I used a different model of External USB battery with the same B&N NC cable, it registered as 500mA, exactly as that particular model is rated. Though your thought is justifiably skeptical (and I'm an unrepentant skeptic myself), further evidence suggests there's more going on than just detecting the additonal pins in the B&N NC cable.
Click to expand...
Click to collapse
I believe the standard microUSB cord has a resistor, or circuitry to limit the amperage to .5. The Nook Color has a charging cable with a higher amperage at 1.9, with a special connection so you cannot put it into another device and fry it. Most modern device have a way of limiting the input internally, but the the Nook's cable is unique on the device end to be safe.
If you would like to test this use a standard microUSB and plug it into the Nooks OME wall transformer and measure the amperage. in my tests it always comes out at .5 amps even though the output of the NC's transformer is 1.9 amps.
I use my muti-tester to avoid erroneous software data.
Certaily would like to test this portable charger you mention in your post, for $13 sounds good to me. This would be handy while I am away from wifi and I tether my Android phone to my Nook, the phone could be plugged into this charger, tethering can really burn battery down fast.
Thanks for the tip!
12paq said:
Certaily like to test this portable charger in you mention in your post, for $13 sounds good to me.
Click to expand...
Click to collapse
I'm going to order that aswell. Has anyone seen other nice accessoires for the Nook color on Dealextreme? Search only gave me a black pouch
tomic22 said:
I'm going to order that aswell. Has anyone seen other nice accessoires for the Nook color on Dealextreme? Search only gave me a black pouch
Click to expand...
Click to collapse
so funny, me too.
Also "CrazyinDigital" from Amazon Canada, even shipped to USA I got a nice Pleather case and a bunch of cables and the silicon cases are decent too. The bulid qualty of the cords is sketchy and the screen protectors don't fit, but I got all the above for $5.19 shipped to the US. I'd pay at least that for the USB cord. (Funny thing the cords say "for Kindle"... gotta laugh.
Back on topic, I might buy this back up charger, sounds good for my battery sucking Android Phone too..
12paq said:
I believe the standard microUSB cord has a resistor, or circuitry to limit the amperage to .5. .
Click to expand...
Click to collapse
Given that the USB battery charging specs give up to 1.8A, that doesn't make a whole lot of sense....
In Battery Charging Specification,[40] new powering modes are added to the USB specification. A host or hub Charging Downstream Port can supply a maximum of 1.5 A when communicating at low-bandwidth or full-bandwidth, a maximum of 900 mA when communicating at high-bandwidth, and as much current as the connector will safely handle when no communication is taking place; USB 2.0 standard-A connectors are rated at 1500 mA by default. A Dedicated Charging Port can supply a maximum of 1.8 A of current at 5.25 V. A portable device can draw up to 1.8 A from a Dedicated Charging Port. The Dedicated Charging Port shorts the D+ and D- pins with a resistance of at most 200 Ω. The short disables data transfer, but allows devices to detect the Dedicated Charging Port and allows very simple, high current chargers to be manufactured. The increased current (faster, 9 W charging) will occur once both the host/hub and devices support the new charging specification.
Click to expand...
Click to collapse
http://en.wikipedia.org/wiki/Universal_Serial_Bus
Divine_Madcat said:
Given that the USB battery charging specs give up to 1.8A, that doesn't make a whole lot of sense....
http://en.wikipedia.org/wiki/Universal_Serial_Bus
Click to expand...
Click to collapse
Yeah I might have .5 volts mixed up with amps.. I posted that late last night, dozing off.. lol. sorry for the any inaccuracies.
I did these tests a while back and should have recorded the data and not left them too memory.. and age.. lol.
I initiated theses tests becouse I found it took much longer to charge the Nook with a generic cord even if I plugged it in the Nooks wall transformer that has a higher output. it could just be my cords too.
My apologies if my careless quoting of data led anyone astray. Funny, I am usually a stickler about accurate data. ..
Lesson: Never quote data from memory late and after a glass of wine..
Thanks Madcat
12paq said:
I believe the standard microUSB cord has a resistor, or circuitry to limit the amperage to .5.
Click to expand...
Click to collapse
.... wat
12paq said:
If you would like to test this use a standard microUSB and plug it into the Nooks OME wall transformer and measure the amperage. in my tests it always comes out at .5 amps even though the output of the NC's transformer is 1.9 amps.
I use my muti-tester to avoid erroneous software data.
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You should have plugged into your fingers. Stop making up nonsense.
Standard microUSB is, well, a standard. And that standard says 500mAh max current. The Nook Color cable is non standard and has 4 extra pins. These extra pins, as well as shorted data pins, tells the Nook Color it can draw 1.9Amps.
I am hesitant to buy something like this since I have read that the USB Micro on the NC is non-standard.
http://www.ebay.com/itm/Barnes-and-...?pt=US_Tablet_Accessories&hash=item19c71f2149
You're smart to worry about these. This one is a simple microUSB cable, not the Nook Color compatible cable which has a longer tip. It will still allow you to transfer data and trickle charge but because of the shorter tip it will not allow a quick charge.
The part that is also important is the plug/brick you plug this cable into. You have to make sure it outputs 1.9 amps so that it is capable of quick charging your Nook Color if you have the correct cable to use. Most usb plug/bricks (like the ones for your phones) will only output about a quarter or maybe half of that. Some Apple iPad/iPhone usb plug/bricks will put out more though.
sjmoreno is right, be wary on these. It shows it is shipping from the inside the United States, but that doesn't mean much as they buy these in bulk from China at a lower price and raise it a bit here. I have ordered a few of these micro USB cables from china eBay listings with varying luck. Some will actually fit, and others won't - some charge REALLY slow and I actually had one that melted on me because it was pulling too much current.
Hey,
If you are still under warrantly, you can call B&N or chat with them on the website and get a new cable, adaptor or a power kit with little or no trouble. Just tell them your current one is not working. You can also go to a Barnes and Noble store and speak to one of the nook guys and you can get a free one there too.
sjmoreno said:
You're smart to worry about these. This one is a simple microUSB cable, not the Nook Color compatible cable which has a longer tip. It will still allow you to transfer data and trickle charge but because of the shorter tip it will not allow a quick charge.
The part that is also important is the plug/brick you plug this cable into. You have to make sure it outputs 1.9 amps so that it is capable of quick charging your Nook Color if you have the correct cable to use. Most usb plug/bricks (like the ones for your phones) will only output about a quarter or maybe half of that. Some Apple iPad/iPhone usb plug/bricks will put out more though.
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Click to collapse
Chargers (wall or vehicle) made for Apple products will only charge at the slower rate. The NC looks at the resistance on the USB data lines to see if it should charge at the fast rate. The resistance set on chargers for Apple products is different than for the NC. The only chargers I've come across for the NC that charge at the higher rate are those made by B&N. Other chargers can be modified to work, but that's a different topic.
wrong...
mrmark93 said:
Chargers (wall or vehicle) made for Apple products will only charge at the slower rate. The NC looks at the resistance on the USB data lines to see if it should charge at the fast rate. The resistance set on chargers for Apple products is different than for the NC. The only chargers I've come across for the NC that charge at the higher rate are those made by B&N. Other chargers can be modified to work, but that's a different topic.
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Wow, you actually sound like you know what you're talking about. (I kid... I kid...)
Here's a photo of my Apple USB plug which I've highlighted puts out 2.1A. I could use this plug with the official B&N Nook Color cable and it will get the quick charge since the extra length of the tip on the B&N NC cable will allow it to reach the 12 pins that are further inside the Nook's outlet. Although I wouldn't do it since it could (maybe, might, don't want to chance it) send too much current to the battery and possibly damage it or over-heat it.
I also have a Motorola usb plug for my Droid X and Atrix phones but that only puts out 850 mA (.85 Amps) which could trickle charge regardless of the cable I use.
Hope this explained it well enough.
sjmoreno said:
Wow, you actually sound like you know what you're talking about. (I kid... I kid...)
Here's a photo of my Apple USB plug which I've highlighted puts out 2.1A. I could use this plug with the official B&N Nook Color cable and it will get the quick charge since the extra length of the tip on the B&N NC cable will allow it to reach the 12 pins that are further inside the Nook's outlet. Although I wouldn't do it since it could (maybe, might, don't want to chance it) send too much current to the battery and possibly damage it or over-heat it.
I also have a Motorola usb plug for my Droid X and Atrix phones but that only puts out 850 mA (.85 Amps) which could trickle charge regardless of the cable I use.
Hope this explained it well enough.
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right back at ya!
Your Apple unit is rated at 2.1A, but will only 'put out' whatever the NC draws from it, up to a theoretical 2.1A (I never measured over ~1850mA during any of my testing). Have you measured the charge rate on your NC? How? Did you load the battery monitor widget, does it report 'AC Charge' with the Apple charger? Are you using the Nook Tweeks app and forcing the fast charge mode? Just curious.
You made some other comments that are misleading, so I'll say my 'opinion' on those:
You could hook your NC to a 5V, 10,000+Amp power supply and not hurt it. The NC regulates the rate of charge with an on-board charge controller, and even if it didn't, it still wouldn't harm the battery. USB is 5V by specification. Apply 5V to a battery currently holding a charge of less than 5V and it will be charged to 5V. When you first start charging, it will charge at the highest rate available (by supply restraint, charge controller, wire size, connector conductivity) and as the battery becomes more & more charged, the charge rate (current flow) will drop, and when fully charged, the current drops to zero (0). The chargers are rated at what they can safely supply, 1A, 500mA, 2.1A, 850mA, etc without damaging the charger itself-some chargers are smart and limit the current, others will supply what they can and suffer damage if more current is drawn than the charger is rated for (ex: Harbor Freight unit with shorted data pins put out 1.1A (rated 0.5A) and started melting parts before I shut it off). I tested an 'Apple compatible' charger rated at 2.1A and it would only charge at around 600mA unless I shorted the data pins, then it put out whatever the NC would draw, up to a measured max of ~1850mA.
Oh, Snap!
mrmark93 said:
right back at ya!
Your Apple unit is rated at 2.1A, but will only 'put out' whatever the NC draws from it, up to a theoretical 2.1A (I never measured over ~1850mA during any of my testing). Have you measured the charge rate on your NC? How? Did you load the battery monitor widget, does it report 'AC Charge' with the Apple charger? Are you using the Nook Tweeks app and forcing the fast charge mode? Just curious.
You made some other comments that are misleading, so I'll say my 'opinion' on those:
You could hook your NC to a 5V, 10,000+Amp power supply and not hurt it. The NC regulates the rate of charge with an on-board charge controller, and even if it didn't, it still wouldn't harm the battery. USB is 5V by specification. Apply 5V to a battery currently holding a charge of less than 5V and it will be charged to 5V. When you first start charging, it will charge at the highest rate available (by supply restraint, charge controller, wire size, connector conductivity) and as the battery becomes more & more charged, the charge rate (current flow) will drop, and when fully charged, the current drops to zero (0). The chargers are rated at what they can safely supply, 1A, 500mA, 2.1A, 850mA, etc without damaging the charger itself-some chargers are smart and limit the current, others will supply what they can and suffer damage if more current is drawn than the charger is rated for (ex: Harbor Freight unit with shorted data pins put out 1.1A (rated 0.5A) and started melting parts before I shut it off). I tested an 'Apple compatible' charger rated at 2.1A and it would only charge at around 600mA unless I shorted the data pins, then it put out whatever the NC would draw, up to a measured max of ~1850mA.
Click to expand...
Click to collapse
You sound more invested in this. I'll go sulk in a corner now...
sjmoreno said:
You sound more invested in this. I'll go sulk in a corner now...
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Click to collapse
Just trying to be helpful
Mess of technical crap from the 'car charger' thread:
http://forum.xda-developers.com/showpost.php?p=16505252&postcount=47
I spent half a day measuring crap to satisfy my curiosity. the reuslt: B&N should have standardized with normal (i-device) charging standards
Hi,
Does anyone know why it is such a god damn crapshoot for charging speeds on the galaxy note 2 (or any samsung device for that matter).'
You buy a charger rated for 2amps and you never know what it will give you.
You buy a USB micro cable and get anywhere between 0.4amps and 1.6amps.
What is the criteria that the phone is using to determine how many amps to pull from the charger? How does it even know what gauge of wire it is? Is there some sort of resistance check?
I have a Galaxy Note 10.1 and that is even more particular than the GN2. With most aftermarket chargers, it absolutely refuses to charge. I've had so much trouble finding a charger for it I've just stopped using the tablet since I only have one working charger for it.
It really sucks spending anywhere between $2-$30 dollars on a charger and not knowing if it will work. My success rate has been less than 10%.
I try to do forum and google searches, but all I seem to find are comments like "I bought this charger. Seems to work." With no detailed information on what performance they are getting out of it.
This is really turning me off samsung products. I don't have this problem with my HTC or LG android devices.
I don't know why you have problems, I have 2 samsung devices (phones) and I chare them with their original chargers, charger from Nexus 7 and my old charger from Desire HD and all work just fine... ofcourse, the original one is the fastest, since it is 2A, HTC one is 750mA and Ativ S one is 500mA, N7 one is 1A....
dalanik said:
I don't know why you have problems,
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Click to collapse
You kind of answer this for yourself, as follows:
dalanik said:
I have 2 samsung devices (phones) and I chare them with their original chargers, charger from Nexus 7 and my old charger from Desire HD and all work just fine... ofcourse, the original one is the fastest, since it is 2A, HTC one is 750mA and Ativ S one is 500mA, N7 one is 1A....
Click to expand...
Click to collapse
Your stock charger is 2A. (about 1.5-2 hours to charge)
Your HTC charger is 750mA (about 4-5 hours to charge)
Your ATV charger is 500mA (no better than a computer port. 6-8 hours to charge)
This was my point. This IS my problem. Obviously the stock charger works at 2A, but with any other charger it is anyones guess as to what speeds you're going to get out of it. Even when they are specified to work at 2A, you are likely not going to get 2A out of it. The phone is so bloody fickle.
If there was some benchmark or specific set of criteria I could use when I purchase a new charger to know for certain if it will charge at 2A, then that would mitigate some of the problem at least. But right now, there is none as far as I can tell. When I purchase a charger, I literally have no idea if it will run at 2A with this phone.
I'm glad that you're not bothered by the slow charging speeds and are happy with <1A. I'm sure this works well for most people. It doesn't for me. I push my phone to the max (as I have every right to) and need a charger that can keep up.
Well, charging slowly is different to what you say i.e. "refusing to charge at all" etc. And of course I don't use Ativ's charger to charge N2 often, it would take ages But I use HTC's charger that is 750mA and it charges within 2 hours which is OK.
Anyways, the only solution for you is to buy BRANDED charger from a company you can trust not some cheap chinese, t should work just fine whether it gives 2A or 1.9A is really no big difference.
dalanik said:
Well, charging slowly is different to what you say i.e. "refusing to charge at all" etc. And of course I don't use Ativ's charger to charge N2 often, it would take ages But I use HTC's charger that is 750mA and it charges within 2 hours which is OK.
Anyways, the only solution for you is to buy BRANDED charger from a company you can trust not some cheap chinese, t should work just fine whether it gives 2A or 1.9A is really no big difference.
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Well, there are chargers that refuse to work. Especially with the Galaxy Note 10.1.
Cheap ebay chargers are a crapshoot, that much goes without saying. But there are many brand-name chargers that don't work at full speed, despite being rated for 2A.
Its not so much a charger thing as a samsung thing. While I'm not able to find specific criteria as to how/why the phone decides to charge at the speed it does (which is really the only question I had with this thread), I can tell you that there are many brand name products (monoprice, anker, ngear, etc) that are rated for 2A, but will not run at 2A with the samsung. They will usually run at 2A with other products though.
The more research I do, the more I highly suspect that this is a case of Samsung propriety. It looks like that they are deliberately throttling aftermarket chargers to force you to buy their overpriced samsung chargers. As I understand it, it has something to do with creating a voltage divider between two of the contacts, but every diagram I find shows a different wiring scheme. This would indicate that no one really knows for sure.
The one and ONLY question I have with this thread is to find out what criteria the N7100 uses to determine how much amperage to draw. I remain confident that no one will answer this question because it seems no one knows.
For the Note 2: there is a way to get a simple measurement of how much current is being pulled. Refer to this thread for the apk and more info.
alpha-niner64 said:
For the Note 2: there is a way to get a simple measurement of how much current is being pulled. Refer to this thread for the apk and more info.
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Thanks for posting this. I suppose I should have mentioned that I have this app already and it is incredibly useful. I also have this, which with only a few bizarre exceptions, reports the same as the app.
The more people who are aware of this app, the better. People who think that their aftermarket charger "works fine for me" are probably unaware of how much those chargers are under-performing.
I don't have the education to explain your situation your situation well. But it boils down the electrical engineering the the physics of electricity.
There are quite a few variables that all effect the charging of devices. First thing is what does the device require for charge input, which is both amps and voltage. For whatever reason, quite a few tablets require 15 volts versus 5, which is what most mobile phones need. I have this same issue with my ASUS Transformer Infinity pad. It requires 2.0amps with 15 volts. I have a Galaxy Note II with needs 2.0amps with 5 volts. Unfortunately, when I use my phone charger with the tablet, it puts out enough to trigger a charger is plugged in (turns on tablet if it is off), but not enough to trigger there is actual charging. It does charge it, but it's a trickle charge; basically if it using while plugged in, it only slows the battery depletion rate.
As for the charge output, now you're getting into build quality, resistance of the components of the charger itself and the USB cable being used.
And then depending the device, the pins used on the USB cable can have an effect too. This mostly occurs with tablets or proprietary cables because the pins may tell the hardware what kind of charger is being used, which may have built in limits for charging.
Hopefully that helps some.
lovekeiiy said:
I don't have the education to explain your situation your situation well. But it boils down the electrical engineering the the physics of electricity.
There are quite a few variables that all effect the charging of devices. First thing is what does the device require for charge input, which is both amps and voltage. For whatever reason, quite a few tablets require 15 volts versus 5, which is what most mobile phones need. I have this same issue with my ASUS Transformer Infinity pad. It requires 2.0amps with 15 volts. I have a Galaxy Note II with needs 2.0amps with 5 volts. Unfortunately, when I use my phone charger with the tablet, it puts out enough to trigger a charger is plugged in (turns on tablet if it is off), but not enough to trigger there is actual charging. It does charge it, but it's a trickle charge; basically if it using while plugged in, it only slows the battery depletion rate.
As for the charge output, now you're getting into build quality, resistance of the components of the charger itself and the USB cable being used.
And then depending the device, the pins used on the USB cable can have an effect too. This mostly occurs with tablets or proprietary cables because the pins may tell the hardware what kind of charger is being used, which may have built in limits for charging.
Hopefully that helps some.
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That last part is correct. I actually know enough about electrical circuits to be pretty sure it is the phone deciding how much power to pull.
Ohms law states that the amperage of a circuit is the voltage of the circuit devided by the resistance (in ohms).
USB circuits are almost universally 5 volts. I remember reading somewhere that a phone has a potentiometer that protects it from circuits of incorrect voltage, up to a certain amount. This is probably why you can get away with sticking a 15V charger onto your phone and not blowing it up. You cannot depend on this however. Generally, you do not want to stick a charger into your device that is a different voltage rating than what the charger is rated for.
The charger decides the voltage, using an internal device that changes AC voltage (120VAC if youre american) to 5VDC (USB) or whatever your device needs. This device is called a rectifier.
As stated above, the charger decides the voltage. The battery determines the resistance*, therefore the amperage is the natural result of deviding the voltage by the resistance.
*Resistance is added to the circuit by the wire and the charger itself, but is usually inconsequential.
When a charger says that it is rated for a certain amperage, that means that it is the maximum amount of current that thr internal components can handle safely, without running the risk of earth-shattering kabooms (fire). If the circuit you have connected to your charger contains too little resistance, you will increase the amperage (ohms law, as stated above), and you may end up with a piece of charcoal where your charger used to be.
Thr fact that the samaung phones can change the amperage of a charging circuit so fickly must mean the phone is capable of changing its resistance. So the question becomes, what criteria is it using to determine when to change the resistancr and to what?
-PW
This may be the longest thing ive ever typed on my phone.
I'm not disagreeing since, as you said, the mobile device manufactures have build in some safe guards so we don't fry them from incorrect chargers or over charging.
But there are charges that are 15v. I've have one that came with my ASUS Transformer Infinity Pad. I think many Samsung tablets are in the same boat. I don't recall using that charger on any of my smartphones; if I have, it's only been once or twice, but good possibility I may never have. But as stated earlier, I have used my phone chargers on the tablet, but only does a trickle charge. That tablet has some wide input plug at the end of the USB cord. I'm thinking one of the pins must not get enough power to trigger the full charge. Yet, if I use my Anker external battery, set it to 15v, and a few adapters, it triggers the normal charge cycle.
Don't forget,phones such as Galaxy Note 2, Galaxy S3, use 11pin microUSB ports versus the standard 5. I have no idea what all pins do or trigger, My assumption, part of your answer why the charge output varies lies with how they're use the other pins. I know quite a few tablets have more than 5 pins since the USB port is some wide thing; the ASUS does because it carries data and power for the separate keyboard that can be attached to be a suedo-laptop that has USB ports, battery and full 104 key keyboard; I don't recall what other ports the attachment may have.
I still hold that part of charge difference is also the USB cord itself since difference materials have difference resistance. It may not be as significant as the charger itself, but I've seen significant differences in charging times or depletion rates (around 10% battery per hour) using MHL adapters purely on the USB cables.
Yes, typing out long replies on the phone's virtual keyboard blows monkey chunks. Thus, I use a blue tooth keyboard instead for those situations. I also have a blue tooth mouse, LOL.
Does Quickcharge 2.0 work with heavy duty charge-only cables, or is there a data component that is needed to get Quickcharge to work properly? I'm about to buy an Incipio Quickcharge 2.0 car charger which doesn't come with a cable, and I would like to get a fast charge cable like this one.
I haven't checked with my meter but a standard cable seems to be working as expected with the Motorola provided QC 2 charger.
Any cable will work as far as I know. I just used my old N7 2013 cable with he quick charger and it worked the same as the Motorola one.
Thanks for the replies but I am talking about a non-standard cable., one that only supports charging, but I think I have an answer now.
I asked a cable vendor, PortaPow, and their response is:
"Quick Charge 2.0 requires a charger designed to Qualcomm's specs and a sync+charge cable. A charge only cable such as this one will only work for charging at 5V."
I see that I misunderstood the question. Yes something has to handle the voltage/current handshake if you want anything to happen. I hadn't thought about it but it would seem that even "charge only" cables must do something with the D pins or you'd see an "incompatible charger" message on most devices.
ok so if we must have specific cables to use with the qualcomm chargers, post them up so i can purchase a couple...
According to the patent (http://www.google.com/patents/US20140122909) it uses the data pins. You don't need a special cable, but you'll need a standard usb cable that has all 4 pins intact.
Monoprice carries cables with 28/24AWG for data/power lines, but only with a bulky ferrite choke on them. Looks like most manufacturers don't list wire gauge for their products.
I would like to find a nice 3FT cable with 22AWG copper wire for power, with low voltage drop.
Roundabouts said:
Monoprice carries cables with 28/24AWG for data/power lines, but only with a bulky ferrite choke on them. Looks like most manufacturers don't list wire gauge for their products.
I would like to find a nice 3FT cable with 22AWG copper wire for power, with low voltage drop.
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Voltage drop isn't worth mentioning with a 3' cable and 22AWG seems like overkill. If anything it'd be adding resistance, no? I realize it's stranded, but still. 24AWG should be more than enough, I'd think.
Edit: Got confused on my gauges.
estallings15 said:
V22AWG seems like overkill. If anything it'd be adding resistance, no?
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Click to collapse
While increasing volume of wire (lower gauge) won't increase resistance we're talking about 5-13V and .5-5A so any cable you might buy that meets USB spec will be fine.
I used the supplied cable and a 10' cable. Neither got warm and both charged at QC2 speed.
Roundabouts said:
Thanks for the replies but I am talking about a non-standard cable., one that only supports charging, but I think I have an answer now.
I asked a cable vendor, PortaPow, and their response is:
"Quick Charge 2.0 requires a charger designed to Qualcomm's specs and a sync+charge cable. A charge only cable such as this one will only work for charging at 5V."
Click to expand...
Click to collapse
I purchased 2 of their compatible cables - http://www.portablepowersupplies.co.uk/portapow-20awg-fast-charge-sync-micro-usb-cable/
and decided to go with Puregear's quick charger - http://www.ebay.com/itm/15149060665...38.l2649&ssPageName=STRK:MEBIDX:IT&rmvSB=true
The Puregear quick charger is small and has a rubbery soft finish.
Do the cables work at full amperage?