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USB charging in car?

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.

Want faster charging/Device discharging while charging/not charging? Read within!

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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Click to collapse
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.
Click to expand...
Click to collapse
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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Click to collapse
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
Click to expand...
Click to collapse
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/
Click to expand...
Click to collapse
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.

Charging Issue: Charging Slowly from USB, Charging Normal from Wireless Qi

Hi everyone, so my issue I currently have with my Nexus 6 is as follows:
Device Details: Nexus 6, rooted, running CM13, Xposed Framework installed
Charging from USB: shows "charging slowly" message on lockscreen. Ampere shows an average of about 200mA, regardless of type of charger. Tried several QuickCharger adapters and a regular adapter, as well as several different cables to the same result. When connecting to a PC via USB, it shows the same charging power, however my laptop is not recognizing that the device has been plugged in.
Charging Wirelessly: charges normal as it always had, showing a average of about 500-700mA.
The issue occurred suddenly while I was out hiking and attempting to charge via a QuickCharge capable portable battery. The previous day it was charging as it always has.
All signs point to a damaged micro USB port on my Nexus 6, but wondering if there could be any other possible causes. I'm hesitant to try a factory reset to troubleshoot it as a software issue since I have no way of connecting it to my PC to re-root and re-flash CM if that doesn't fix the issue.
If it is the micro USB port as I think, any suggestions on how to remedy this? I'm used to using my device heavily everyday and charging it with a QuickCharger as needed, so this slow charging is a significant issue right now.
Thanks for any help!

your phone charges at differing speeds at differing parts of its charging cycle. and on top of that, charging via usb instead of wall charger will carge your phone at a much slower rate. that said, we also have a "usb fastcharge" option included in many kernels/custom roms. but you also have to know that fastcharge doesnt work with every usb port that you can plug into. it only will work with certain usb ports.

simms22 said:
your phone charges at differing speeds at differing parts of its charging cycle. and on top of that, charging via usb instead of wall charger will carge your phone at a much slower rate. that said, we also have a "usb fastcharge" option included in many kernels/custom roms. but you also have to know that fastcharge doesnt work with every usb port that you can plug into. it only will work with certain usb ports.
Click to expand...
Click to collapse
Sorry, I should have been more clear. When I said "Charging via USB" I just mean through the phone's microUSB port. Regardless of whether it was plugged into a wall charger(with or without QuickCharge 2.0) or my laptop or a portable battery, or a QuickCharge car charger, I was getting the same charge rate and message showing "charging slowly", much slower than wireless charge rate which showed the normal "charging" message. The Qualcomm QuickCharge 2.0 using the provided Motorola Supercharger or my QuickCharge 2.0 capable portable battery has always worked great prior to this issue.

mrkb510 said:
Sorry, I should have been more clear. When I said "Charging via USB" I just mean through the phone's microUSB port. Regardless of whether it was plugged into a wall charger(with or without QuickCharge 2.0) or my laptop or a portable battery, or a QuickCharge car charger, I was getting the same charge rate and message showing "charging slowly", much slower than wireless charge rate which showed the normal "charging" message. The Qualcomm QuickCharge 2.0 using the provided Motorola Supercharger or my QuickCharge 2.0 capable portable battery has always worked great prior to this issue.
Click to expand...
Click to collapse
ok, because the included "fastcharge" is only for usb charging. but regular charging still depends on where in the charging cycle you were. for example, at 92 itll charge at a much slower rate than at 50. what battery percent where you at when you noticed?

simms22 said:
ok, because the included "fastcharge" is only for usb charging. but regular charging still depends on where in the charging cycle you were. for example, at 92 itll charge at a much slower rate than at 50. what battery percent where you at when you noticed?
Click to expand...
Click to collapse
Initially very low, under 15%. Was attempting to charge with a QC2.0 portable battery, but the device was draining quicker than it was charging. When I got home, I attempted the Motorola "Turbocharger" wall charger and got the same rate. So I put it on the wireless charger, and as it charged, I kept testing the wall charger every 20% or so, getting the same slow charge rate.
The bottom line is really that the Wireless Qi charging is functioning properly as it always has, but any "plugged-in" type charging is charging at an extremely slow rate, no matter what type of charger, no matter what % the battery is at.

mrkb510 said:
Initially very low, under 15%. Was attempting to charge with a QC2.0 portable battery, but the device was draining quicker than it was charging. When I got home, I attempted the Motorola "Turbocharger" wall charger and got the same rate. So I put it on the wireless charger, and as it charged, I kept testing the wall charger every 20% or so, getting the same slow charge rate.
Click to expand...
Click to collapse
odd! it could be a software issue or just a derp. have you tried rebooting? im one of the few that i know with a broken usb on my n6. and it charges slower. it used to charge at about 2400mV, now it charges at 800mV max. now that its completely broken, i cant charge it via a usb anymore, now i charge it wirelessly, which is at about 800mV max as well. anyways, try a reboot, or reflashing your software first, before doing anything extreme.

simms22 said:
odd! it could be a software issue or just a derp. have you tried rebooting? im one of the few that i know with a broken usb on my n6. and it charges slower. it used to charge at about 2400mV, now it charges at 800mV max. now that its completely broken, i cant charge it via a usb anymore, now i charge it wirelessly, which is at about 800mV max as well. anyways, try a reboot, or reflashing your software first, before doing anything extreme.
Click to expand...
Click to collapse
Yea I've tried rebooting like 20 times lol. Also tried doing a CM nightly software update. I'll see if reflashing will do the trick. Any suggestion on reflashing from the device? I've always used Nexus Root Toolkit and did it from my PC.
If that doesn't work, guess I'm stuck with wireless charging too. Thanks for your help!

mrkb510 said:
Yea I've tried rebooting like 20 times lol. Also tried doing a CM nightly software update. I'll see if reflashing will do the trick. Any suggestion on reflashing from the device? I've always used Nexus Root Toolkit and did it from my PC.
If that doesn't work, guess I'm stuck with wireless charging too. Thanks for your help!
Click to expand...
Click to collapse
you can flash cm via twrp recovery on your phone, without a computer. oh, and my work buddies are still in shock that my n6 wirelessly charges.. they both have iphone 6s

How do I tell if I'm quick charging? Is there an app?

I have my original Nexus 6 charger that supports the Qualcomm Quick Charge 2.0. But I don't have the usb cable any more... or don't know where it is. I heard that you have to have a quick charge compatible cable. I have a TON of cables, and I'd like to try them out on my quick charger, but I'd like to know if quick charge is working at a quick glance. Is there a way?
-Peter

Download Ampere app from Playstore, once you open it, it'll start measuring your charge rate. It'll also tell you if it's turbo charge, you can also tell it's fast charge if you get like 1800-2000+ mAh.

I'm using the cable from my old '12 N7 with my N6 charger... charges to full in about 90 minutes or so (from 10% to 30+% in about 15-20 minutes). I'd say feel your device after about 5-10 minutes of charging... if it's as hot as hot tap water, you're probably quick charging. When I charge with other chargers, it gets warm , but not hot.

thanks guys. i downloaded Ampere late last night. in a nod to both of you, when quick charging, Ampere was showing about 2200mA and when regular charging, it was showing about 650mA. and when quick charging, it was noticeably hotter.
i thought that you were supposed to use special quick charge cables, but i tried a handful of different cables this morning on my N6 quick charger and they all would charge at or above 2000mA. if anyone knows any specific info about cables, i would love to read about it, but otherwise i'm pretty happy that i'm quick charging again.
-Peter

The only specific info regarding cables is to avoid "charge only" types, which are frequently found with Logitech products. Charge only cables have the two center pins disabled, which neuters the quick charge system. In quick charging, power is sent through the data lines (the two center pins) as well as the power lines, which results in a faster charge.
There is no way of telling you have a charge only cable just by looking at it. It has to be plugged in.

Some cables, like the one in this pic have the awg or mm sq size on them.https://goo.gl/photos/5ni5wofvnaBUpot6A
I'm willing to bet the larger wire (24 awg) is carrying the charging current.

More great info, guys thanks a bunch

Correction of QC functionality
Strephon Alkhalikoi said:
Charge only cables have the two center pins disabled, which neuters the quick charge system. In quick charging, power is sent through the data lines (the two center pins) as well as the power lines, which results in a faster charge.
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This statement is wrong, power is never never send over data lines ever anywhere!
QC needs data lines to communicate with the device, because QC3 for example charges with up to 20 V / 2.5 A and if you hit a normal phone with this voltage, it might fry the charging controller.
Actually the charger and the device handshake over the data lines, so the charger knows it's OK to send out that much power (over the power lines).
A non-QC device won't answer to the handshake and therefore the charger will send out the standard 5 V.

@kabinx: After nearly a year I'm not going to press the issue too much because after so long I can't remember the source of my information about the data lines being used for charging, but where did you find your information about quick charge?

Slow Charging - Max Charging Amps?

So I recently picked up a T813 to replaced my Nexus 7 (2013), I've had a few weeks now, and as with all my devices I slow charge it. This tablet generally took ~30 hours or so to charge at 0.35-0.45 amps, but I didn't think anything of it. This week I went on a trip and plugged it into a charger that can output anywhere from 0.8 to 1.8 amps depending on the port you are using (all the current ratings I'm listing are what I've measured, not what the devices are rated). My tablet said "Charging" at first, but then once it hit 75% all it would say is "Charging Slowly" no matter what. Now that's all it will say. Sometimes after a restart it will say "Charging" briefly, but then it goes back to "Charging slowly". The charger I was trying to use was an Anker product, so not a complete "no-name" charger.
I did some more checking and it appears my tablet has an upper charge limit of 1.5 amps using even the factory charger which is rated 2.0 amps. That same factory charger plugged into my Nexus 5X outputs 1.88 amps. Anything less than 1.5 amps, my tablet behaves as the rest of the devices. If I plug the tablet into a power source that current is limited to 0.5 amp, using the same cable, using an Honor 5X, and the Tab S2, both draw the ~0.5 amp.
Now the "Charging" and "Charging Slowly" messages were on Lineage, however since I have returned home, I and done all the subsequent testing, I have used Odin to return completely back to the factory Samsung software. Right now I have some videos playing to run the battery down, and am planning to trying to charge the battery all the way up using the factory charger to see how long it takes. If it also takes 30 hours, I'm going to assume it has to be a hardware problem?
Anyone else have any ideas?

My T813 arrived with Nougat on it. The only Odin firmware I could find that would successfully flash was a Marshmallow so I let videos play overnight (which did actually play overnight surprisingly!) to fully drain the battery. This morning I started charging the battery with the OEM charger, and from fully dead to 100% it took roughly 4.5 hours. So I would say this is normal from what I've read. I would say this rules out any hardware issue.
My next test will be to find a flashable Nougat OEM image as it doesn't want to update itself. Then see how it performs then. I'm starting to wonder if Samsung changed something in the firmware to make it charge slower on purpose just to prevent any "Note" like issues from happening? Finally then I'll have to also go back to Lineage, as I don't plan on using it at all with the stock software, as it's quite unbearable. There's a reason I only buy devices that Lineage is available for.

So after updating to Nougat, and letting it update, then fully draining the battery again, which again took overnight, it seems to charge even faster. This time from 0-100% taking just under 4 hours using the OEM charger, at roughly 3 hours 45 minutes.
I'll put Lineage back on it tonight, however this definitely calms my concern that I had a hardware issue. It's definitely fine. I'll see what kind of charge time I get with Lineage.

It charges with ~1600mah

I've had slow charging issue twice. I sent it in the first time and Samsung sent me a slow charger (not fast charger) to use. Worked fine for about 10 months. Once I update to Nougat, my charging became slow again.
Seems like many people have slow charging issues with this tablet. I have the Verizon tab s2 9.7

Extreemator said:
It charges with ~1600mah
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Click to collapse
Yeah this is what I've noticed. This seems to be about the upper boundary. Despite being shipped with a 2 amp charger. I did reinstall Linage, and it charges fine with the OEM charger, so it's not a bug on their end, or a hardware problem for me. With LOS and the OEM charge it's still ~4 hours to charge with is what I would expect roughly based on my other tests, even though LOS still reports charging slowly.
I think my problem early with the 30+ hours of charge time was related to the hub I was charging with. I have been having issues where I would wake up and my phone wouldn't be charged at all. Most nights it would though, so I figured my cable was starting to go bad. Swapped the cable and same issue. Measured the current on the ports, and it was far below what it should be on a USB port, the charge ports were getting 0.18-0.2 amps, the regular ports were 0.2-0.3 amps (not sure why the regular ports were getting more). Then I noticed the power adapter was not plugged in all the way into the wall. After plugging it in all the way the current on those ports returned to normal. This honestly doesn't make any sense to me, so it maybe time to replace that hub. Either way, I know the problem is not the tablet, which calms my fears about it, since it was the new piece of hardware.