yashsingh1/xdaforums huggingface dataset:
[Galaxy S 4 General] flash608:
Ekhem... hold your horses mate ;) How do you think car/wall charger or PC/laptop as you have written earlier can support 1900mA of power if for example PC/laptop USB output has only 450/500mA ?? I know that the app shows 1900mA but it`s not true. Read about USB ports in wikipedia --> "Charging ports and accessory charging adapters" http://en.wikipedia.org/wiki/USB

The app shows 1900mA cause it thinks it`s connected to power USB when data lines are connected.

Sorry for my english
[Galaxy S 4 General] Woodski:
It's simple. I know how long it takes to charge x% on a normal USB port

And I can see how much faster it goes after disconnecting the data lines to my Thinkpad.

Based on that I believe the indication that this apps gives is roughly correct.

Charging time on a USB port of a T400 series Lenovo is now 54% in 60 minutes (from 2% > 56%) with the dongle

Just do some reading before you write that fast charge is not possible.
[Galaxy S 4 General] agonysfate:
As i know and as it says om my laptop specs. It support current up to 1A , i made a module instead cutting wire, but my app was telling the truth, laptop cant supply all current that my mobile requires, my laptop current protection worked and prevented high current supply otherwise ill lose my USB port,

Can you do a research and use an 'ammeter' to indicate how much current flow you got really, try to take a photo, i did in my earlier posts.

Sent from my GT-I9500
[Galaxy S 4 General] beehman:
Anyone have experience with the Antec quad poart usb charging station UA4-25?

Per the specs it looks like it has a max output of 5A the most I've seen for a multiport charger...

I can't post external links yet since I'm a new member...

---------- Post added at 08:50 AM ---------- Previous post was at 08:32 AM ----------

This item is available on amazon...
[Galaxy S 4 General] 2hard2read:
For the record.

I had a knockoff car charger, and it was only giving it 340ma (the phone said it was on AC), so I got a dual 2.1 a charger, and I also got a single 2.1 charger, I tried both with different USB cables, and I get 1200ma or 1900ma. Now I'm satisfied.

I even have a 6ft extension at work with a mini USB-Micro USB adapter and I get 1200ma consistenly, the OEM cable didn't make a difference.

The OEM S3 cable is the only one that made a difference, it was giving it 960ma.

With 1200ma I was able to use Navigation with screen on and charge battery.

At home I have a Vizio adapter (got it on clearance) that goes up to 2.1, and it gives it about 1200 or 1900, with the S4 cable or other cables but the S3 cable.

I think it is a good idea to get the app and check your phone.

by the way , is there another app that shows the charging amps?
[Galaxy S 4 General] sofakng:
Is it possible to purchase additional (OEM) Galaxy S4 USB cables? (so I can use my 3rd party 2 AMP chargers)

...or does anybody know where I can purchase pre-made USB cables that will support the 1200/1900mA charging? (I don't want to hack up a cable and tape it back together, etc)
[Galaxy S 4 General] 2hard2read:
I bought a $2.39 cable on ebay and get 1200-1900mA.

I'm using a 6ft USB extension with a MINI-Micro USB adabpter with no issues I get 1200-1900.

The only cable that doesn't give me over 1000, is the OEM for the S3. I get 900 with that.

UPDATE: I just tried a cheap 6ft cable, and only got 600mA. So one more to the list, it was also thinner than the other ones.

good luck.
[Galaxy S 4 General] Jaekryl:
Possible alternate solution to the problem

Instead of scouring Amazon and eBay for potentially good quality cables and charging blocks, would it be possible to fix this issue through the kernel? Does anyone know of a kernel/ROM that removes these charging restrictions?
[Galaxy S 4 General] Woodski:
The phone needs a proper voltage to charge. With a high current the thinner cables will have a voltage loss that is too high.

So don't blame the phone or kernel and get a good (short) cable.
[Galaxy S 4 General] agonysfate:
For galaxy S4:

The mobile try 2 times in one second after you connect power on, if mobile's ic detect any voltage drop.. it will restrict current drain, and this is for both mobile and charging source protection , keeping it safe from malfunction or even burn.

Sent from my GT-I9500
[Galaxy S 4 General] Jaekryl:
Thanks for the clarification. I didn't realize 1900 mA was such a high current. Looked into my previous phone, and it turns out the Galaxy Nexus only takes up to 900 mA, so I've never had to deal with high charging currents before.
[Galaxy S 4 General] Chuke01:
Hi, can you tell me the name of the app in that capture. Thanks mate.
[Galaxy S 4 General] Lebada:
So which cables charges properly without degrading over time (1900) and is available in the US?

I see somebody tested with the Blackberry Thick Cable, but that is Canada only.
[Galaxy S 4 General] tzuik:
DIY cable for charging in car

1st of all, you can ask your local electronics supplier for a proper cable like this one if you don't want/know how to do a thicker one by yourself: http://datasheet.digitus.info/en/4016032292005.html

The S4 requires a thick cable to be able to draw enough current. You can do a quick computation with the ElectroDroid App, section Voltage drop calculator and it will show you the following results:

Copper cable with 15AWG and 5VDC input, with a length of 1m and a load of 1900mA will have 20.404mV drop (0.41%) up to 4.98V

So I got a 2x15AWG stranded copper cable with 1m length from my local electrics store, I went to my local electronics store and purchased a male USB A connector and a male microUSB connector like the ones in the attach. I soldered the ends of this cable to each + and - of each connector then I made a bridge between data + and data - on the microUSB connector. Now I have the best cable you can possibly get only for charging in car. I have a cheap 2xUSB charger (2.1A) and I put a Y USB adapter for maximum current draw from each port. No fuss.

It is indeed a pity we can't draw over 1.2A when using the device as a GPS in car because I use a spider podium as a holder that keeps the phone in the vents and with AC on, the phone is dead cold even with screen on.
[Galaxy S 4 General] rahlquist:
The theory is sound if the phones needed 5v to charge but the S4 battery is only 3.8V (single cell design I would believe) so anything beyond 4.2v is likely superfluous and will be cast off as heat in voltage regulation in the devices charging circuit to protect the battery from over voltage that would shorten battery life. ref.: http://goo.gl/tuPYy

Given that information and the calculation you mentioned you can see that a 3 foot 28awg cable still has a nominal output of approx 4.2v at 5v & 1.9a in. ( http://goo.gl/mdJSCm )Very similar to the stock cable for the S4. The 28/24awg Monoprice cables I mentioned earlier have a voltage output of approx 4.4v at the same power levels and the 6 foot length I use ( http://goo.gl/rNIyo5 ).

Your 15AWG cable is very efficient but is likely overkill considering the needs of the device.
[Galaxy S 4 General] DarkStarr:
My S4 can and will draw 2A in the car just fine. I simply use a Duracell dual port adapter. 2A max, 1A per port with 2 devices plugged in or 2A with only one.

Also the S4 seems to work with the Apple chargers since I have an iPad charger that my tablet could only draw 1A from and the S4 is claiming a draw of 2A.
[Galaxy S 4 General] tzuik:
I am now using 4.3 Google ROM and it draws 1900mA in the car also when used as GPS with the sreen on. It seems Google didn't implement the reduced current draw when screen is on in it's kernel :D
[Galaxy S 4 General] esqueue:
Most car chargers what have attached cables only use 2 wires for their chargers. I took apart a Rocketfish 2A charger, replaced the cable, and added the 2 82k ohm resistors according to the schematic in the first page. It charges 1900 when the screen is off.
[Galaxy S 4 General] djcristi:
my findings are :

galaxy s4 (i9505) , charging current reported by Charging Widget

the original charger has 5.08V , and 1.2V on Data lines.

but the S4 will not specially need 1.2V on D-lines, just them joined (D- connected to D+). because i have made several tests with or without 1.2V on these lines, makes no difference, it will still draw maximum (1900mA).

the phone during charger connection will raise the current until the voltage drops to an acceptable minimum of ~4.85V and stay at that current. if the voltage drops a little and then raises, the current will raise too.

for example: i connected to a lab power supply (variable voltage) a female USB A connector (with D+ and D- joined) .

-test 1: i set the voltage to 5.1V on the supply . using the original S4 usb cable i was getting 1320mA reported current. i raised the

supply voltage to 5.5V and bingo, 1900mA current.

-test 2: same situation, generic microusb cable : i have to raise the voltage on the supply to 6V to get 1900mA... (so much voltage drop on USB Female connector...)

strange , when S4 reports 1900mA charge, on the lab supply it shows only 1720mA load... and when the screen turns off it shows 1540mA load... so i guess it's not so real the 1.9A load shown on the phone...

after, i connected the same generic microusb cable to S4 original charger, guess what... 1900mA .... (and this cable doesn't even have Shield connected)

Conclusion: original cable is so good, because it has Shield wire connected (so it doubles as a GND wire, helping to reduce GND track resistance) and because it has good quality USB A connector (same is the S4 charger USB connector) . It's important that the pins inside the USB connector make good contact (low resistance).

so if you want to use a generic 2A car charger or home charger, it's important that the charger has good quality USB connector . a sollution if you use a generic China 2-port 2.1A ipad charger (around 2-3$) to make an usb cable that connects to both ports (i was able to get only 1.2A connected with single port with original S4 usb cable) to get the maximum current . Don't forget first to connect D- to D+ inside the charger.

Or if you use good quality charger and get maximum current with original cable but not with other cables, that because some low quality cables have thin wires inside, low quality connectors , and don't have Shield connected (which would've improved GND wire thickness , lowered it's resistance). I have several 1$ usb-microusb cables around, using them with original charger i got currents like 300mA-700mA, so crap....
[Galaxy S 4 General] djcmn:
Interestingly enough

My car charger for my old Verizon LG 8950 that I had in 2009 ( Ugh Verizon, ripoff artists, thank god I am on T Mobile now) charges my S4 SGH-M919 at the full 1900 mA.
[Galaxy S 4 General] rahlquist:
Thank you so much for this info, you helped me troubleshoot a new toy I picked up. ( http://www.kickstarter.com/projects...ter-know-your-power/posts/666684?ref=activity ) the tl;dr is the Practical Meter measures the current (displayed as calculated power) via a 200 milliohm shunt resistor. At 2A this would drop 0.4V across the PPM sinc ethe S4 determines how much current it can pull by the input voltage it wil cause the s4 to not pull the full 2a..

So unfortunate side effect is my new toy causes the S4 not to charge at full rate. :(
[Galaxy S 4 General] djcristi:
i'm glad that it helped you.

it's normal to happen that stuff, any resistor that you put in series , will drop voltage...

The best way is to measure with a Charging Widget because it will not affect the input. Even with the original charger and cable, sometimes i have to plug it in 2-3 times to get 1900mA reading... Keep in mind that the widget shows that amps that the charger can do (detected) , not the actual amp draw...
[Galaxy S 4 General] amilayajr:
RE: Galaxy S4 Charger

I use a Galaxy S3 Charger for my S4 and it works fine. I hate the fact that the charging for S4 is too fast. Charging too fast is not that good since it depletes the battery faster. If I can remember correctly the S3 chargers are rated at 1A. I'm not sure how techy the S4 charging network are but they might implemented the USB cable mechanism to avoid using fake or cheap cables. It really is the voltage that will drive the current not the other way around. Heck you can charge the phone with 0.5A as long as the voltage is 5V it will be slow but it should still work unless samsung implemented a current sensing network then that's a different story. Running 2A on the line is not really a funny thing, can get hot quickly. This is probably a reason some of these units burn while charging
[Galaxy S 4 General] djcristi:
your knowledge about battery charging wear is outdated. Li-ion batteries need to be charged at their designed charging current. As the battery has larger capacity (mah) the current can be higher . If the charging current is very low , the battery will not reach the end of charge voltage (4.2v) and will overcharge (causing it to be blown sometimes after high current drawn).

And the fast charging current does not actually get the phone/bat hotter, since it implements qualcomm's quick charge specification, which has very low loss in conversion (5v -> charging voltage )
[Galaxy S 4 General] AxlxA:
Thank you so much for this post. I was wondering why my S4 was charging so slowly at home. I was using my Jambox's usb cable(I used it cause it was the longest one) for charing up my S4. It was only giving me about 1A =(. I've tested ALL my other cables now and found the original samsung cable and 2 others are working fine. In fact, I've checked my car's 2 port 2 + 1A charger and finding that the cable does make a huge difference. When I used to run GPS/bluetooth navi on my S4, it would actually end up discharging 1% every 20 mins or so. I later figured out that the cable I was using was only giving it 660mA to 900mA. Since then I've switched back to my 3 year old thick bulky USB cable, 2A all the time on ANY charger(except iPad charger).

I used to app "Galaxy charging currrent lite" to see what current it was getting.
[Galaxy S 4 General] m14mclaren:
I have a charger for my S4 that uses a 12v battery from one of the power tools I own, it basically has a usb port on it, if I plug in my S4 cable and it charges my old S2 fine and says its charging from AC in the settings, however when I plug it into my S4 nothing happens. Would this be due the the resistors and is there anyway I can make it charge? It would be really handy for when camping etc.
[Galaxy S 4 General] abusalem:
My S4 is only 8 months old and the battery is totally screwed up. It holds the charge for not more than 5 hours while it used to last a full day easily when I bought the phone. Also the charger has malfunctioned. It won't even charge the phone. The problem is that accessories have a 6 month warranty. So i have no other way than buy a new battery and a new charger. S2 quality was top notch. With s4, Samsung has lost respect in my eyes at least.
[Galaxy S 4 General] amilayajr:
You mean it needs to be charged at their designated voltage as well???? it can't go pass beyond 4.3V and can't be charge for prolong period of time at that voltage. As for fast chargers. They only fill up to max of 70% of your battery but won't reach saturation voltage or end of voltage to accomplish full charge. Although, these batteries preferred to be not fully charged anyways. And yes, fast charges increases temperature of the battery because your dumping more current into it. Increase in temperature degrades the battery life. I did an experiment between two samsung chargers. one is rated at 1A @ 5V and the other is 2A at 5V. The 2A definitely makes my charger and phone feel warm but the 1A works great and doesn't even feel warm. If you trust qualcomm's specification for quick charge that much go ahead. As far as I'm concern, I want to get the best out of my battery's life at least 2 years if not, more max of 3 years.
[Galaxy S 4 General] MattBooth:
I'm glad I found this thread. Though I was going mad. I noticed the lead from my SGS3 charged much, much slower than the supplied white cable in the box. I even went as far as getting more stock cables for my wall points (all 2A Samsung power sources).
[Galaxy S 4 General] Spud37:
Okay So I am looking at purchasing chargers and cables. From reading this thread it looks like the S4 charges at 1.5Amps or so, with the correct cable. I am looking at purchasing a new cable for my phone and tablet.

I was wondering how do you know if it was one of the good usb cables that is shielded correctly? Anyone know a brand to trust for USB cables?

Do I need to purchase Samsung cables to use for my devices or is there another brand that would work? Also looking at Wall chargers. Currently the Anker Quad Port looks good. It has 2 USBs at 1.5 Amps and 2 at 2.1 Amps. The 2.1 Amps for my tablet and the 1.5 Amps for my phone. Would it be bad to put the phone into the 2.1 Port?
[Galaxy S 4 General] Hoffsil:
Cable

I use LG cable and works fain.
[Galaxy S 4 General] Arkain2K:
Excellent thread! Thanks for all your findings!

Cheap generic micro USB cables will more than likely maxes out at 300ma, wheras third-party charge/synch cables especially made for smartphones will have no problem with 1900ma.
[Galaxy S 4 General] KnifeHead:
The current is more high if screen turned off, its arround 1900.

You can check it with galaxy charging current, make fast move from turned screen off, on again and press refresh.

I use rooted stock rom i9500ubueml1 with stock kernel.
[Galaxy S 4 General] Pfeffernuss:
With some custom kernels, like the one in my sig, you can also charge @ 1900 with the screen being on as you can see:
[Galaxy S 4 General] jasonhcloukey:
cable matters

Tried some different combinations...

Samsung stock wall charger + Samsung stock USB cable = 1200mA

Samsung stock wall charger + older USB cable(has the letter "B" on the end) = 300mA

Samsung stock wall charger + Enercell® retractable cable = 1900mA

All values are with screen on.
[Galaxy S 4 General] fransarj:
Need help on this one. I have a SPIGEN 2A fast car charger paired with an original Samsung U2 (5pin) cable. I'd normally get 1200 which is acceptable enough till i find a better cable, but the Samsung U2 suddenly started acting weird after i used it on a generic power bank. Since then, Anything I try to plug it to (Computer USB, Spigen 2A, Samsung S4 original charger) it would show a consistent 460ma on the Galaxy Charging current app.

What went wrong here?

Thanks!

Edit: Here's what the spigen charger looks like: http://www.spigen.com/accesories/sgp-compact-car-charger-kuel-p12q-c-series.html
[Galaxy S 4 General] jaswinky:
You must use a cable with data pins bridged for using with Samsung phones. There are some blogs and posts here to make it yourself, but you need a good quality cable to get 1,9A. Once bridged the cable, you won't be able to use it for data, just for charging.

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---------- Post added at 06:03 AM ---------- Previous post was at 05:57 AM ----------

With the correct combination wall charger and cable, s4 charges at 1,9A, you can use 2,1A port, but if your wall charger is not ready for Samsung devices, you need to mod the cable to simulate a Samsung wall charger, otherwise you will get only 650mA.

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---------- Post added at 06:25 AM ---------- Previous post was at 06:03 AM ----------

Sorry, but you are wrong with the speed charging. You'd right if you were speaking about old Ni-Cad batteries, the slower charging, the better, but for new Li-ion batteries, the faster charging, the better for its life duration, since they have no memory. The reason is that, while they are ready to support high amperage, while it is charging battery temperature gets high, worse thing for all batteries and a direct cause for decreasing its life, so as less time you have the battery charging, better for its life being the best to charge it as faster as you can so that temperature affects the battery for a shorter time. Using a 1A charger will get the battery hot during double time than using a 2A charger.

You can read a lot of articles over the Web about new Li-ion batteries myths like this one.

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[Galaxy S 4 General] c-st:
Yes and you make another one up yourself. The batterie gets hot because of its internal resistance and the higher the current the hotter it gets. (Hotter is worse) And yes, NiCd had a memory effect, that is why you should empty the cells before charging. If you charge them 14h without control you need a low current, if you charge them fast you need at least a charging current of 1x C (apacity) for the electronics in your charger to be able to detect a fully charged batterie.
[Galaxy S 4 General] jaswinky:
I didn't write anything about temperature differences with amperage differences, so i didn't write opposite you did, of course hot is due to resistance, but having the battery 2.30 hours hot is rather worst for its life than having it just 1.15 hour with only some more degrees without any hot dissipation or ventilation (you can check the temperature difference is in both cases 1A and 2A is very poor).

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---------- Post added at 02:13 PM ---------- Previous post was at 01:51 PM ----------

Yes, i referred to that, old NiCd batteries had memory and as you write it was bad to charge them before almost 100% capacity was discharged, and it was better a slow charging. Opposite, with new Li-ion batteries as our s4, it is not needed let the battery completely discharged before plug in the charger, and it is better a fast charging due to expose hot the battery for a shorter time.

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[Galaxy S 4 General] slowfuse:
Excellent post

Great post, thanks for taking the time to document your findings.

I bought a wall charger with 4x 2.1A USB ports here in Hong Kong.

Unfortunately appears to be dud and provides a max of around 1.2A and dropped back to 900mA (where Samsung chargers provide an initial 1.9A and like your findings drop back to around 1.2 or 1.3A).

I also found the cables varied greatly. Yep, cheap were crap.

..and the original cable that came with my S4 didn't work as well as a newer, longer, thicker cable that came with a later model Samsung charger that I bought separately.
[Galaxy S 4 General] chickentuna:
Guys i have a question, my S4 charges at 1.2a when the screen is on. 1.9a when the screen is off.

Now the phone still charges at 1200ma when the screen is on but when it's off, it no longer charges at 1900ma. Sometimes it charges at 1400ma, 1380ma, 1600ma, 1800ma being the highest. I need to re-plug the charger 2 or 3 times to get 1900ma. Often times i don't get 1900ma charging rate at all.

I am using the app currentwidget to monitor the charging rate.

I should mention that the I had my charger replacement about 2 or 3 months ago. Before it got replaced, I was experiencing the same thing but with lower charging mA's when the screen if off/on.

My question is, is this behavior normal? Is the charging rate degrading over time? What do I need to do to get a consistent 1900ma charge when the screen is off?
[Galaxy S 4 General] jaswinky:
Change the cable. A lot of stock white s4 cable have come a bit defective, worst cases in this forum have affected not only to the charging current but also issues while flashing with odin.

Another thing, s4 always (if both charger and cable are ok) gets 1,9A, both with the screen on and off, what happen is that current widget measures on battery input, and if screen is on (and not in deep sleep cpu state) , the net current to the battery is 1,9 minus screen and cpu consumption (about 0,5-0,6A depending on the app and brightness).

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