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I'm having problems with kaiser charging when using HSDPA and even slow connections like 3G and EDGE.
Problem is that it charges for about 20-30 minutes (connected to a powered 1Amp USB hub or even with AC charger), then charging light goes off and battery power starts to drop by about 5% every 20-30 minutes.
Have anyone tried 2Amp chargers? It seems like it may be the problem with kaiser itself, since it charges itself but then just stops and will not charge itself until I soft-reset it.
PS: it gets kinda warm, but I wouldn't call it hot. Dunno if its related to temperature.
Any ideas?
Am I the only one with this problem? If so, maybe I should return the phone and exchange it for a working unit?
No, I have the same problem here.
When I use my kaiser in the car (usually navigating) the orange charge light initially lights up, but after a short period goes out. When I disconect and connect the USB-cable, the light temporarily comes on again.
I am using a 1A car charger. I do notice the charger feels a bit hot when in use, so maybe the kaiser is drawing more power than allowed? I can imagine the charger overheating which causes the voltage to drop. Which probably causes the kaiser to stop using USB power. But this is all speculation.
I am planning to use a 5A voltage regulator to 'upgrade' the USB charger, and see if this solves the problem.
--After a bit more reading, I found some info about the kaiser detecting if it is connected to a charger or a USB host device, and regulating it's maximum charge power accordingly. So I will try a modified USB cable to let the kaiser know it can get 1000mA from the car charger.
It's not the USB charger. I have 2A and 3A Olympus Camera chargers that I modified to use as a USB charger. Also cheaper 1A AC chargers. I thought the Olympus chargers would be perfect, because they were high amperage, and built solidly. I had the same charge problems with the TyTn II, and an iPod Nano. They would either charge partially and then stop, or not charge right away, but the charge light would come on after awhile. But still only partially charge.
My guess is that the chargers that work may have a load added in, so that the switching regulator will turn on with any additional load from the device, and stay on. I never found any information on this, though.
What does work: The USB chargers made for any PDA phone. Apple iPod chargers. I bought an 800ma iPod charger (probably a clone). It's a small white cube, with a USB outlet, and interchangeable AC plugs. It charges the Nano, and the TyTn II OK. The Nano last for a week now, instead of 2 days. The TyTn II starts charging right away, and stays charging. So whatever the Apple USB chargers do, they do work.
A thought for the car is to get a car charger made for the iPod, and see if that may work.
To be more accurate, the iPod charger starts charging the TyTn II right away, and the charge light stays lit. I've not actually done a controlled test on it. Just charged for awhile, and verified that the charge light comes on right away, and stays on. Everything looks normal, though. I will try a more controlled test, and post the resutls.
please keep us posted. I've also contaced HTC support about this, I'm waiting the response. Once I found out I will post here.
Hopefully iys not a ksier limitation.
Test results.
Battery at
- 61%, Display off while charging
- 83% - after 70 mins of charging. Then stopped, as was going out.
Started again at:
- 88%, Display off
- 100% - after 60 mins. A little shorter, probably, as I missed when the charge light went green.
I believe the PDA will fast charge up to around 80%, and then slow charge for the remainder. That would explain why it takes 60 mins to charge from 88% to 100%.
So, the iPod charger works great for a PDA, and will start charging right away when it is connected, and it will charge to 100% full charge. It is not the PDA that is stopping the charging. It just has special requirements that only some chargers can handle, so you have to get either a charger built for a PDA, or something like the iPod charger.
So it works quite well as a general purpose charger for iPods, and for the TyTn II, and probably anything that uses a USB charger. It is small, with interchangeable AC plugs. A good travel/general purpose charger. I can bring just this, and different cables for different devices. Phone, MP3, etc.
It is labeled Input:100-240V, Output 5V 1A
Looks like:
Apple MA592LL/A iPod USB Power Adapter
Just as an aside, I have a lithium battery pack 2 7/8" x 2 1/8" x 1/2" thick. It is rated at 2400mAh, input 5V, through a built in retractable USB plug. Output is 5V 450mAh through a female USB plug. Just extend the USB male plug and plug into any USB source to charge it. It works quite well as a small portable battery pack to power/charge a PDA if using GPS steadily. It's flat, and easy to carry.
And it is quite cheap.
ttt123, thanks for your info. I guess I need to get an iPod charger then.
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.
Click to expand...
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.
Click to expand...
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.
As many of you, I struggle with charging my Note.
I've recently bought a 2.5A charger but struggling to find a good cable that can handle it. When using my stock charger with it and playing games etc. my battery slowly depletes. I did buy a cable from the same company as the charger that is designed for the higher power and does work as expected, makes charging quicker and actually charges while playing games, the only problem is the connection is loose a slight move of the phone and it stops charging.
So does anyone have any recommendations and success stories when charging their note?
For those curious this is the charger: http://www.amazon.co.uk/PortaPow-Qu...=UTF8&qid=1365954674&sr=8-1&keywords=portapow
Hi folks,
We're getting ready for a cross country trip. 2 kids, two tablets. One is a Samsung Tab 2 that charges via usb connected to a standard 12V-to-USB car charger just fine. The other tablet is an Asus TF701t. When connected to the regular USB cable for it, plugged into the 12V-to USB charger, it says "not charging." So I read up through Google and found the ASUS tabs have special requirements.
I just bought an: Asus Eee Pad Car Charger Power Adapter,36 pin 15V 1.2A Power Adapter Travel Car Charger for ASUS EeePad TF600 TF600T TF810C TF701T (Car Charger)
I plugged it in, and the tab still says "Not Charging."
Now, it IS charging a bit... despite the battery window saying not charging, I see the green timeline indicator that shows charging, and after a few minutes it went from 91% to 92%.
But I'm concerned this will be just a trickle of charging and not stand up to constant use. We've got two days of driving, 8 -10 hours per day, and this tab is my 8 year old's primary entertainment.
Given this is the official car charger for the tab, why won't it show proper charging?
My plan B is that the car does have a built-in 110V outlet. I could plug the wallwart into that (though, I need an extension cord, because the wallwart is too big to fit in the small recess where the 110V line is). I'm a bit worried the wall wart will pull too much juice through the 110V line and cause it to shut down (thermal protection).
Experiences or thoughts that might help me here?
Marc
Yeah sounds like it can't supply the correct voltage. More likely it is supplying 11V and the tab really wants 15V to charge. (Car batteries are 12V so unless it has some sort of transformer in it which is unlikely). So it will be a slower trickle charge.
Compare the car's inverter rating (the 110V outlet) with the input rating on the Asus charger. Mine wants 0.5A at anything from 100 to 240 volts, so if your car outlet is rated 120 watts or better it will do. If you are handy with a soldering iron there is a simple alternative: chop off a female USB cable and splice it into an automotive 12V power plug. Assuming your car's alternator and regulator are healthy (and of course battery) it will put out 14.0-14.5V at cruising speeds, perfect for charging Asus TFs. If your car has a 12V power outlet; many don't come with cig lighters anymore, but most have the same hole somewhere with a rubber plug in it. Word of warning though: make sure the kids don't plug the Samsung (or anything but a TF) into the modded 12V USB port, it will let the magic smoke out. They are only rated for 5V.
Turns out the car charger charged the tablet fine despite the not charging status. We started the trip at 9:30 with 75% charge. Two hours later, with constant game use, the tablet was nearly full. Stayed that way throughout the day's drive.
Thanks all.
Sent from my SGH-M919 using Tapatalk
Yesterday I've received my Tab S2 8.0". After the first charge I connected the tablet to my computer to upload some files and I get a red "X" on the battery and the message: "Slow charger connected"
In the notification area I get a constant red "Device charging slowly. To charge faster, use the original charger".
Is this normal? Cause I'm using the USB cable that came with the device and tried with USB3.0 and USB2.0 with the same results.
Oh, extra info! The tablet was bought in France, I'm from Argentina.
XinsaX said:
Yesterday I've received my Tab S2 8.0". After the first charge I connected the tablet to my computer to upload some files and I get a red "X" on the battery and the message: "Slow charger connected"
In the notification area I get a constant red "Device charging slowly. To charge faster, use the original charger".
Is this normal? Cause I'm using the USB cable that came with the device and tried with USB3.0 and USB2.0 with the same results.
Oh, extra info! The tablet was bought in France, I'm from Argentina.
Click to expand...
Click to collapse
Yes it's normal.
USB ports cannot put out as much current as a decent charger (like the one the tablet came with). Hence it charges more slowly using USB (or indeed some inferior or lower powered plug-in chargers), and it's warning you that it is doing so. I think the maximum a USB2 port can provide is about 500mA, with USB3 about 900mA or so.
Compare that to the proper plug-in charger, which is 2A (if I remember correctly).
Some motherboards etc do have higher current USB ports for charging etc, but that's non-standard and they are usually specially labelled as such.
Oh, thanks for the help. I got a little scare with the warning.
I got the same tablet, and also noticed this warning about battery charing slowly, and asking me to use original charger.
It's working resonably ok with original charger, though it charges slow with other chargers with the same AMP rating. E.g. it charges slowly with the larger iPad charger, which is also 2 AMP rated ...
Charing with iPad charger is so slow, that when I use the device with during charging, it drains faster than it charges! Quick unusual ...
Anyone? Any comments?
Theres an excellent app called Ampere which gives you info on the tablets charging and power consumption - useful and interesting.
Cant post links yet so just search for it on Play
Also don't forget that (when not built-into the charger) the cable is also important to the amount of current reaching the tablet.
The best charger in the world may well struggle if a long cable with hair-thin high resistance wiring is used to transfer the power into the tablet.
Lastly even though many chargers are labelled as 5v 2A, they may not actually be able to provide that under load, and if things drop when a hungry device like a tablet is connected then things will slow up.
I have a few 5v 2A chargers which come up as slow charging, whereas others which were more purposefully designed (e.g. the 5v 2A charger from my old Nexus 7) work just as well as the supplied Samsung one.
DarrenHill said:
Also don't forget that (when not built-into the charger) the cable is also important to the amount of current reaching the tablet.
The best charger in the world may well struggle if a long cable with hair-thin high resistance wiring is used to transfer the power into the tablet.
Lastly even though many chargers are labelled as 5v 2A, they may not actually be able to provide that under load, and if things drop when a hungry device like a tablet is connected then things will slow up.
I have a few 5v 2A chargers which come up as slow charging, whereas others which were more purposefully designed (e.g. the 5v 2A charger from my old Nexus 7) work just as well as the supplied Samsung one.
Click to expand...
Click to collapse
this is such onfortunate ongoing issue
i got my Tab S2 - SM-T715Y in Thailand as i am backpacking Asia ..
I know the warranty is per country .. so I can not use it where I am now - in Vietnam .. or back home in USA
I realized that this was a major factor before buying .. so I can go through my credit cards extended warranty ..
in the future I will buy Acer or Asus or alike that have international warranty ..
yesterday I was on a road trip
and I was using my 12V car charger
and then a battery bank .. and I think it rigered this problem or fact that I drained my S2 to 0%
fact is that now it is showing "slow charger connected" .. I am using the original charger and cable
now it is slowly *discharging* when connected to AC!!
also will try to whipe the cache..
this is so terrible
I am losing faith in Samsung :/ (had charging issues with my Note 3 .. 8 months in .. motherboard issue)
I can not find a solution to this problem
I am thinking of putting it in a refrigirator? maybe it will do something to the battery?