Database Users

Nexus 7 : USB Power Behavior

Is there any information about the USB power behavior for the Nexus 7?
The official Nexus 7 answer is to use their wall charger.
Background info:
By default USB provides 100mA per port.
With host negotiation it can provide 500mA per port.
Apparently the Nexus 7 wall charger provides more, anybody know what it is?
Does the Nexus 7 respect the USB BC 1.1/1.2?
What is the power situation for the four side contacts?

Not sure about all of this but the official charger is faster than usb because it runs at 2 amp. which is much more than a usb 2.0 normally will provide

Source of info?
lamboboy732 said:
Not sure about all of this but the official charger is faster than usb because it runs at 2 amp. which is much more than a usb 2.0 normally will provide
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Do you know it is 2.0 A because you hooked a meter to the charger/android pair while charging or is there a source for this info?

phreede said:
Do you know it is 2.0 A because you hooked a meter to the charger/android pair while charging or is there a source for this info?
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The charger itself has 2.0A written on it for Output

phreede said:
Do you know it is 2.0 A because you hooked a meter to the charger/android pair while charging or is there a source for this info?
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Yes read the charger. 5v 2amp.
IPad charger is the same 10watts.
Sent from my Nexus 7 using Tapatalk 2

Charging Issue?

So I am coming from a Galaxy Nexus and was trying to use the little 1amp Samsung chargers from that. Noticed the bundled charger provides a bit more output at 1.8 amps?
Anyways, switched to the bundled charger but the phone complains at me unless I use the bundled cable. Any ideas?

MoNsTeReNeRgY22 said:
So I am coming from a Galaxy Nexus and was trying to use the little 1amp Samsung chargers from that. Noticed the bundled charger provides a bit more output at 1.8 amps?
Anyways, switched to the bundled charger but the phone complains at me unless I use the bundled cable. Any ideas?
Click to expand...
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Simple. The other cables cant handle that current.

FynxSyndct said:
Simple. The other cables cant handle that current.
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Mhmm never thought of that I guess since never ran into that problem.
Also been using this 15ft monoprice cable for ages and it cant seem to handle it. Bummer since its handy to have this cable in my room.
http://www.monoprice.com/products/p...=10303&cs_id=1030307&p_id=5460&seq=1&format=2

FynxSyndct said:
Simple. The other cables cant handle that current.
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I don't think that's true, I had my charger and cable from my Note 2 which is a 2 amp charger, and that didn't allow my G2 to charge at full speed either.

MoNsTeReNeRgY22 said:
Mhmm never thought of that I guess since never ran into that problem.
Also been using this 15ft monoprice cable for ages and it cant seem to handle it. Bummer since its handy to have this cable in my room.
http://www.monoprice.com/products/p...=10303&cs_id=1030307&p_id=5460&seq=1&format=2
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Click to collapse
This is frustrating to me. I also had one of those monster monoprice cables. I used it for my Galaxy Nexus and then for my Galaxy S3.
Does anyone have a long USB cable that will charge this phone? If so, where did you get it? What kind is it?

drathian1 said:
This is frustrating to me. I also had one of those monster monoprice cables. I used it for my Galaxy Nexus and then for my Galaxy S3.
Does anyone have a long USB cable that will charge this phone? If so, where did you get it? What kind is it?
Click to expand...
Click to collapse
Longer the cable, the more lose there is....
Sent from my LG-D800 using XDA Premium HD app

drathian1 said:
This is frustrating to me. I also had one of those monster monoprice cables. I used it for my Galaxy Nexus and then for my Galaxy S3.
Does anyone have a long USB cable that will charge this phone? If so, where did you get it? What kind is it?
Click to expand...
Click to collapse
Emailed monoprice support, will see what they say.

I'm having the same issues. All of my microUSB cables give me the error. Anybody know of rated cables that will work? Seems crazy that I get the error with every single one of my cables, but not with LG's bundled cable. I've used these cables to charge a DNA, GS4, HTC One, Nexus 7, etc. with no issues at all.

Might be a long shot but could vzw/att have a setting in the build somewhere that causes this? I know it's a long shot but we all know how greedy they are.
Sent from my Nexus 7 using Tapatalk 4

Isn't this phone equipped with some type of different usb that allows for faster charging? I think I read that somewhere. The other cables may not have the proper viber/wires to handle the current...
** I have no idea what I am talking about by the way**
Sent from my VS980 4G using XDA Premium 4 mobile app

craigbailey1986 said:
Isn't this phone equipped with some type of different usb that allows for faster charging? I think I read that somewhere. The other cables may not have the proper viber/wires to handle the current...
** I have no idea what I am talking about by the way**
Sent from my VS980 4G using XDA Premium 4 mobile app
Click to expand...
Click to collapse
Are you thinking of the note3?
http://www.sammobile.com/2013/09/05...-connector-for-faster-transfers-and-charging/

MoNsTeReNeRgY22 said:
Are you thinking of the note3?
http://www.sammobile.com/2013/09/05...-connector-for-faster-transfers-and-charging/
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No referring to the "quick charge"
http://m.pocketnow.com/2013/08/07/lg-g2-features
Sent from my VS980 4G using XDA Premium 4 mobile app

Just an FYI, the blackberry Playbook micro usb charger works great on this phone. 6ft cord, 1.8 amps, can be had for 8 bux.

sam2c said:
Just an FYI, the blackberry Playbook micro usb charger works great on this phone. 6ft cord, 1.8 amps, can be had for 8 bux.
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Do you have a link for that? Cant seem to find it for $8

http://www.ebay.com/itm/RIM-Blackbe...S_Cell_Phone_PDA_Chargers&hash=item4d1268005e
MoNsTeReNeRgY22 said:
Do you have a link for that? Cant seem to find it for $8
Click to expand...
Click to collapse

Thanks, I'll give it a shot!

When I used the LG charger & cable my phone charges the fastest I've ever seen any phone charge before.
Anybody know where to buy certified Quick Charge 2.0 chargers/cables? I know my DNA had Quick Charge 1.0 and I loved it, but I could never find more chargers or cables that supported it.

Same here. 50% to 100% in an hour and a half.

Keep in mind that there is a benefit to battery longevity when charging at lower currents.

MoNsTeReNeRgY22 said:
Emailed monoprice support, will see what they say.
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Click to collapse
So heres what they said.
Thank you for contacting Monoprice.com. In regards to your inquiry, the USB specification limits the length of a cable between USB 2.0 devices to 5 meters (or about 16 feet) and for USB 1.0 the limit is 3 meters (which is about 10 feet.) The longer the cable the more power it would require to charge devices and sync. You might need a active USB cable since the LG phone would require more power. At this particular length the power would charge slower. What is the the length of the OEM cable from LG that you're using? With the 1.8A charger with the 15ft cable still slower compared to the shorter USB cables?
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Can you use a regular USB charger?

Can you use a regular micro usb charger in place of a 3.0 cable?
Thank you for the help

Yes, no problem. In fact with my S5 there is only a usb 2 cable supplied.

admiral70 said:
Can you use a regular micro usb charger in place of a 3.0 cable?
Thank you for the help
Click to expand...
Click to collapse
Yup, you sure can.
Just an FYI: The USB3 cable is in fact micro USB as well. It's just the USB3 version of microUSB. The USB3 port on the phone is backward compatible, so a USB2 cable will work just fine in there. :good:

Yep it will work
Sent from my SM-G900P using Tapatalk

So which will charge quicker the stock charger or my nexus 7 charger?
I think they are both 2 amp chargers. What is the advantage of the extra plug on the charger?

bhess said:
So which will charge quicker the stock charger or my nexus 7 charger?
I think they are both 2 amp chargers. What is the advantage of the extra plug on the charger?
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It's USB 3.0. You'll get faster data transfer speeds when plugged into a USB 3.0 port on a computer.

bhess said:
So which will charge quicker the stock charger or my nexus 7 charger?
I think they are both 2 amp chargers. What is the advantage of the extra plug on the charger?
Click to expand...
Click to collapse
faster data transfer rate.

OK thanks.
So the charging rate is the same depending on the "block" amps?

I think the USB 3.0 charges faster even if it's still the same 2A charger
Sent from my SM-G900P using Tapatalk

bhess said:
OK thanks.
So the charging rate is the same depending on the "block" amps?
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Click to collapse
It would seem so, yes. In re: max charging amps, it seems that the S5, much like the Note 3, will charge only at 1200mA while the screen is on and 1800mA otherwise. See discussion here: http://forums.androidcentral.com/sa...48184-galaxy-note-3-max-charging-current.html
To the OP, thanks for starting the thread... I hadn't even realized that the new Micro USB 3.0 connector actually was backwards compatible with the older MicroUSB 2.0 for charging!

Great link thanks!

Yep Confirmed!

Is there a way to lock the phone into USB 3.0

My phone will not stay in usb 3.0 mode. Is there a way to force it to stay in usb 3.0 mode? This makes a big difference in charging speed on my laptop. Almost 4 x the charging current is supplied in usb 3.0 mode.
Sent from my SM-G900W8 using Tapatalk

bimmerdriver said:
My phone will not stay in usb 3.0 mode. Is there a way to force it to stay in usb 3.0 mode? This makes a big difference in charging speed on my laptop. Almost 4 x the charging current is supplied in usb 3.0 mode.
Sent from my SM-G900W8 using Tapatalk
Click to expand...
Click to collapse
4x the charging current? lol no. Try 2x at peak.

the problem is probably your laptop. why isn't it supplying the additional amperage for usb 2.0?

bloodrain954 said:
4x the charging current? lol no. Try 2x at peak.
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Save your lol. It depends on the computer. In USB 2.0, my computer is supplying 96 ma. In USB 3.0, the charging current 384 ma, which is 4x as much, as I stated previously.

Isriam said:
the problem is probably your laptop. why isn't it supplying the additional amperage for usb 2.0?
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I give up, why? Maybe it was designed that way. If I knew, I wouldn't be asking.

bimmerdriver said:
I give up, why? Maybe it was designed that way. If I knew, I wouldn't be asking.
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Click to collapse
go to a laptop forum? the phone and the cable speed and phone have nothing to do with stock charging. usb 2.0 and usb 3.0 can both charge at "384ma" like you stated. your laptop just refuses to do so.

bimmerdriver said:
Save your lol. It depends on the computer. In USB 2.0, my computer is supplying 96 ma. In USB 3.0, the charging current 384 ma, which is 4x as much, as I stated previously.
Click to expand...
Click to collapse
Charging at 384ma would take about 4 days to charge your phone. Check your currents and try again.

Using Samsung Fast Charger To Charge Phone?

So I my moto charger got destroyed by my dang dog and I'm using a Samsung Fast Charger that came with my wife's note 5. It just says "charging" and its still very slow. It's 2.0a at 5v I believe or 1.6a at 9 or 10v. Yet its still slow. Any recommendations? On marshmallow.

Can anyone help shed light on this?

nellycruzz said:
Can anyone help shed light on this?
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Click to collapse
That's not a qc charger. Hence the slow charging. It's 5v only whereas quick chargers also do 9 and 12 volt.
Sent from my SM-T810 using Tapatalk

nellycruzz said:
So I my moto charger got destroyed by my dang dog and I'm using a Samsung Fast Charger that came with my wife's note 5. It just says "charging" and its still very slow. It's 2.0a at 5v I believe or 1.6a at 9 or 10v. Yet its still slow. Any recommendations? On marshmallow.
Click to expand...
Click to collapse
I don't think the Samsung ones use quick charge 2.0. Even though the galaxy s6/note 5 can use quick charge 2.0 capable charger. I think they use a proprietary Samsung fast charge tech in their own chargers.
So it would charge your phone but at the regular 5v2a. I would recommend getting a quick charge 2.0 capable charger. I have a couple from tronsmart and they are great.
Sent from my XT1575 using Tapatalk

Well I've used the Samsung charger and it says "5v @ 2.0 and then says 9v @1.6. I have it hooked up but its so very very slow. I'm getting 2% charge every 30 mins or so. I ran ampere and I'm getting 3.7V and its stuck on " charging via USB". Anyway to change that from USB to AC? THANK YOU guys for chiming in. I have 6 cords and 3 bricks, 2 Samsung and one of.

My note 4 chargers power charges my MXPE and fast charger.
Sent from my XT1575 using Tapatalk

My s6 charger works great on my moto x style... In 15 minutes i get almost 25% battery!moreover the phone recognize it as turbopower...

Ok hooked up to Samsung charger from note 5. Anything look wrong?

nellycruzz said:
Ok hooked up to Samsung charger from note 5. Anything look wrong?
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Click to collapse
It's showing 'usb charger', which should be very very slow...
you sure you are connected to a wall charger?
It should say 'AC Charger'

I have the power brick in the wall and cable running from it to the phone.

nellycruzz said:
I have the power brick in the wall and cable running from it to the phone.
Click to expand...
Click to collapse
He means a proper fast charger will show AC charging. USB charging means slow.
Sent from my SM-T810 using Tapatalk

dottat said:
He means a proper fast charger will show AC charging. USB charging means slow.
Sent from my SM-T810 using Tapatalk
Click to expand...
Click to collapse
Well shouldn't the Samsung Fast Charger, charger the phone faster?

nellycruzz said:
Well shouldn't the Samsung Fast Charger, charger the phone faster?
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Click to collapse
Not if it's the typical 5volt 2amp version. Couple that up with the fact the moto X pure is picky about what quick chargers even work with it period and you have a harder time finding one that works.
Start by reading this thread.. then get yourself a replacement that has been reported to work with this phone.
http://forum.xda-developers.com/mot...oto-x-pure-quick-charge-2-0-woes-3rd-t3206718

dottat said:
Couple that up with the fact the moto X pure is picky about what quick chargers even work with it period and you have a harder time finding one that works.
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For what it is worth, the Asus quick charger that came with my ZenFone2 charges the MXPE like a champ. Is there a better spot for me to share that information?

jaysus145 said:
For what it is worth, the Asus quick charger that came with my ZenFone2 charges the MXPE like a champ. Is there a better spot for me to share that information?
Click to expand...
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The thread I linked above is where I found the two I ordered and just received.
Sent from my XT1575 using Tapatalk

http://www.amazon.com/gp/product/B00QEX83LA?psc=1&redirect=true&ref_=oh_aui_search_detailpage
I have the Aukey quick charger as my office spare, and it works quite well. Not as fast as the motorola turbo charger, but quite faster than regular 2A chargers.

Guys or ladies, got a new charger from Motorola and it charges "charging USB" and its slow as hell charging. Any ideas? Stock marshmallow.

I got a new Motorola fast charger sent to me but I plug it in and I get "charging over USB" and charging very slow. Why? Stock marshmallow.

nellycruzz said:
Guys or ladies, got a new charger from Motorola and it charges "charging USB" and its slow as hell charging. Any ideas? Stock marshmallow.
Click to expand...
Click to collapse
If it isn't the Turbopower 25 like this one then that's your problem. The phone might not be getting enough voltage.

Link is dead but its this one