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Hi guys,
since the charger of the iPhone has an USB connector, my question is if I can use that charger for the Nexus One too??
Since it supplies actually the same energy level (both can get energy from a PC USB instead), does this mean that also the charger delivers current with good specifications for the N1?
thanx in advance
exelero
How are you going to plug the iPhone 30 pin in to a micro USB? Maybe I'm not understanding you correctly.
to plug the microUSB-to-USB cable of the Nexus One into the USB socket of the iPhone charger.
moto1907 said:
How are you going to plug the iPhone 30 pin in to a micro USB? Maybe I'm not understanding you correctly.
Click to expand...
Click to collapse
I think (s)he means the mains adapter part with the USB socket in it - in which case yes it will work, you just need the right cable - which came with your N1
Looking forward to when all manufacturers standardised on micro usb, for a while I thought that mini usb was micro, so I was surprised to see that the n1 was different then I found out....
ok, now i see. Not enough coffee yet,lol
scote said:
in which case yes it will work
Click to expand...
Click to collapse
yeah, from the connection part, I know it will work. my question was more related if the iPhone charger delivers the appropriate current (tension/amperage) conditions for the N1 and, let's say, it won't burn the N1 due to a too high voltage, or mess up the battery due to an incorrect tension input.
I was just having a conversation on chargers with a friend of mine the other day and googled around on the subject on amperage/current/Ma of chargers..
I stumbled upon these posts (either here on XDA, Androidforums or other forums):
1. "The current rating on a voltage source is the maximum amount that the power
source can deliver without exceeding its saftey rating.
What this means is that if you are using some device that has a power supply
with a current rating of 500mA then its best not to use a different power
supply(at the same votlage rating) with a lower max current rating. i.e.,
anything < 500mA. Now ofcourse you might be able to get away with it but if
it burns down your house then its your fault.
A device will only pull the amount of current that it uses(assuming it is a
voltage controlled device) and this is true regardless of the current
rating(hence the saftey issues I discussed above). If a device
says(sometimes they don't) it uses 500mA then it uses 500mA. Maybe it
doesn't use 500mA all the time but the engineers have put that rating there
for a reason. Using any power supply with the right voltage and a current
rating of anything more than what the device uses is ok because the device
will only pull the current it uses.
Now, about the voltage rating: The voltage rating does not have to be exact
and different devices can tolerate different voltage ratings. The problem
usually is one of current. By increasing the voltage, say, you increase the
current the device uses and then you have changed the parameters that the
device was created with."
2. "And as far plugging your phone into a charger that outputs well over 850mA, don't worry about that either. Unlike voltage, the more amperage the merrier because the device will only take what it needs of the available resources."
3. "Moral of the story. Match the Voltage (5.1Volts) Meet or Exceed the 850mA rating. (which is .850 Amps) and you'll be fine."
4. "amps are not pushed but drawn
amps is the max the charger can provide
before it get pressured and lover the volts
you could use a 5volt 10000MegaAmp charger
and the device would only draw the amps the device
was made to draw all the rest of the amps would stay
at your electricity company
ohms law state Amps == volts / residence"
5. "amps are not pushed but drawn
ohms law state Amps == volts / residence
In other English:
P = VI, where
P = Power of device (watts) and is fixed
V = Voltage used by device (volts) and is fixed
I = Current (amps) and is decided by P/V (a fixed ratio)
So the device cannot draw more current than the fixed ratio. It may draw less current if the charger cannot supply the highest amount, but then as in one of the above posts, it simply takes longer to recharge.
With these devices, milliWatts/miliAmps are the scale, 5V is generally the fixed Potential Difference.
Used in a vehicle, the device is generally both drawing and expending energy (ie. charging and running say, GPS) simultaneously. This in/out situation when prolonged is the cause of the observed overheating with the original X1 battery."
Click to expand...
Click to collapse
Bottom line... Make sure the voltage is 5V, the amperage doesn't really matter.
thanx for your feedback.
both chargers have the same output (5V, 1A) - so I am already successfully using it.
blackberry storm also has micro-usb
hello two chargers and an extra usb-cable
To answer the OP's question...
yes it works fine. I have one in my car and charge my ipod and nexus at the same time without issue. The advanced zune car adapter also works (in case one of the 5 who own a zune are reading this ).
I have been using my old Iphone white plug -> USB adapter for almost a month now and I haven't had any issues.
I tried using the iPhone charger but it charges slow...it does not quick charge. Am I doing something wrong?
uhohhotdog said:
I tried using the iPhone charger but it charges slow...it does not quick charge. Am I doing something wrong?
Click to expand...
Click to collapse
no. If i'm up to date, and i think i am, you'll only get the 'fast charge' if you use the charger that came with your phone. the usb to usb micro chargers all charge slow
Can i use X10 mini charger (5v DC 850mA output) on nexus one by the things i read i understand that i can't but my english is not very good. Thanks
if youre talking about using the iphone usb cable on your n1, HAHAAHHAAHAHAHAH
if you mean using the usb-to-AC adaptor then yea you can use any usb cable to charge anything pretty much..
I have older chargers for that output 5.0v / 550mA and have noticed that the Captivate outputs 5.0v / 700mA.
1. Can I safely use the older, 550mA chargers with the Captivate and what will the effect be?
2. Can I safely use the Captivate's 700mA charger with the older phones and what will the effect be?
Thanks.
1. Yes, you can use it. But it will charge slower.
2. Yes, you can use it. I believe that just because the charger output is higher amperage doesn't mean that it will affect the phone adversely. Think of it this way: A lamp is plugged into the wall outlet at your house. That outlet is rated at 120v 15A. The bulb isn't using all 15 amps, so no problem. But if you were to turn the voltage up or down, the lamp will get brighter or dimmer respectively.
The Captivate can take up to a 1A (1000 mA) charger.
Truceda said:
1. Yes, you can use it. But it will charge slower.
2. Yes, you can use it. I believe that just because the charger output is higher amperage doesn't mean that it will affect the phone adversely. Think of it this way: A lamp is plugged into the wall outlet at your house. That outlet is rated at 120v 15A. The bulb isn't using all 15 amps, so no problem. But if you were to turn the voltage up or down, the lamp will get brighter or dimmer respectively.
The Captivate can take up to a 1A (1000 mA) charger.
Click to expand...
Click to collapse
Another question. You sound smart on this so how about using the nexus one car charger on this? Fits perfect and I don't see why not, but still Leary. .. what do you think?
As long as it puts out 5v, (which is USB standard), you are fine. The amperage is only relevant if the device REQUIRES it. For instance if the device draws 1A and your charger could only handle 550mA your device will charge very slowly.
On the other hand if your charger can handle 1.2A and your device only draws 700mA, then your charger will only output 700mA.
The important thing is the voltage, it needs to be 5v +/- 3% ...
I actually use a generic car charger I bought at walmart with 2 USB ports on it, and it works well for every USB powered device I own ... ZUNE, iPOD, phones etc.
OK. Thanks for the reply. I had read that a phone requiring 700mA that uses a 550mA charger could damage the charger and possibly the phone. That's what made me wonder. And that's what led to the question.
Let's make this a bit more interesting. There's a local, highly-reputable cell phone repair store that has stopped selling car chargers because, they say, the rapid charge is not good for the phone's battery. Their recommendation is to use an inverter (no, they don't sell them) so that you can then plug a standard wall charger into it or a USB cable if the inverter is so equipped. The AC current that results from utilizing the inverter is more consistent than the current flowing from a car charger. So...I purchased an inverter for less than $20 and use it to charge the Captivate in my car.
OK ... not sure we need to get this far down in the weeds on this but here goes ....
The USB2 standard for power distribution is 5v and the thresholds are 4.4-5.25V.
Power is supplied in units of 5v power ... 1 unit is 5v at 100mA, no device can draw more than 5 units from any one port. If you have ever seen a portable hard drive with 2 USB connectors it is because it requires more than 500mA to operate and by using 2 ports the device can draw up to 1A. For dedicated chargers the 4.4-5.25v still applies but shorting the D+/- and disabling the data connection allows the device to detect that it is connected to a dedicated charging port and draw a maximum of 1.8A.
In keeping with the above guidelines, when connected to your computer the Captivate can draw no more than 1 unit of power which is [email protected], when connected to a dedicated charger the phone can draw [email protected] and stay within the standard. (yes, it caps itself at 1A, I know).
OK ... the next bit is going to be hard to digest because there are plenty of examples to the contrary ... there is a standard for mobile USB chargers, and it requires wiring them as dedicated charging ports. What this means to us is that, in theory anyway, a mobile USB charger should allow a device to draw up to 1.8A from it (highly unlikely ... but that's the standard as written).
Here is the problem, if the device is plugged into a dedicated charging port and tries to draw it's maximum rated current, that amount of current may not always be available or it may fluctuate. This fluctuation is what causes problems. Have you ever turned you car stereo up real loud and seen your headlights dim in beat with the music? Same thing, the power system is being drawn down. There are a couple of ways to stabalize your power system ... install a large capacitor (mine is 2 Farad) to provide "conditioning", or go the transformer route.A tansformer provides conditioning, but only on its own outputs... while a large cap will condition the entire power system if installed correctly.
So yes, using a quick charger on your phone can cause issues if your car has a ****ty power system or a large stereo system which is not set up properly (again, ****ty power system). Make sure your charging device is within the standard, and you should be fine wether it is USB via a cigarette lighter port or a 110V transformer.
I appreciate your detailed, helpful reply.
Other than the important 5v parameter, what I've taken away from your information is that a car charger can be used in a vehicle with a power supply that is known to be stable, and that either a whole-car conditioning system or an inverter should be used on one with a, shall we say, "less than stable" power supply (PG version ).
Jack45 said:
I appreciate your detailed, helpful reply.
Other than the important 5v parameter, what I've taken away from your information is that a car charger can be used in a vehicle with a power supply that is known to be stable, and that either a whole-car conditioning system or an inverter should be used on one with a, shall we say, "less than stable" power supply (PG version ).
Click to expand...
Click to collapse
Pretty much ...
There's more than one way to skin a cat, and that Transformer will cost you a whole lot less than a 2 Farad capacitor. I hate cats, but they serve a purpose.
@Battlehymn - one more question for you
I have converted from iPhone to the captivate (no haters please) - finally found a physical form factor with specs i like and the captivate rocks.
Anyway, I have some extra external batteries I used with my iphone that i want to use with my Captivate. I just bought a Female iPod connector and I am planning to connect it to a micro USB connector - the pinout is straight forward, but here is my question:
Should I connect the D+/- (short them together)? That is my plan. My batteries are 1900 or 1000 mAH - I assume that even if the phone tries to the draw 1.8A, the batteries have a circuit to only discharge so fast.
HI everyone, hope thats the right forum
I have in my possession an iphone 4 charger, and since i dont have a dedicated G2X charger i was wondering if it is possible to charge the LG phone with Iphone charger?
thanks!
Well I thought iPhones use same charger as ipods which has a lot wider plug than an android charger. But if that's changed and it fits than plug it in and find out.
Sent from my LG-P999 using xda premium
I don't see it working unless you have some sort of an adapter. The G2x uses a micro USB port, and the iPhone uses a proprietary port.
please see bellow what charger i have. just need to plud the USB cord in the charger, since it have USB input.
so, technically it should work, but will this affect the battery in the long run? i mean, maybe the voltage\current values are different.
If it is a USB adapter then it should conform to USB standards and would then work. I think most of the previous responses assumed you meant a charger with the iPhone tip.
Sent from my LG-P999 using Tapatalk
The idea itself will not work, you can pick one up from Amazon or eBay for pretty cheap.
Sent from my LG-P999 using xda premium
Actually it's likely it won't work. Compare the amps on the G2x charger vs. the iPhone one (and just about any other generic USB charger). All the one's I have are different, lower, and don't work with the G2x. One of them, for some odd reason, makes the touchscreen not work at all when plugged in.
lilaliend said:
Actually it's likely it won't work. Compare the amps on the G2x charger vs. the iPhone one (and just about any other generic USB charger). All the one's I have are different, lower, and don't work with the G2x. One of them, for some odd reason, makes the touchscreen not work at all when plugged in.
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Click to collapse
That is not correct, iphone charger will work technically, however it will reduce your battery life over time due to iphone charger are 1amp while g2x charger is 0.7Amp. Amps must meet to properly charge at the pace selected by manufacturer and battery specs. Lower amp takes time to charge, higher amp will charge fast but will reduce life.
Sent via MIUI-G2X
Mine is rate for 1AMP.
Sent from my LG-P999 using xda premium
nycelitemaster said:
That is not correct, iphone charger will work technically, however it will reduce your battery life over time due to iphone charger are 1amp while g2x charger is 0.7Amp. Amps must meet to properly charge at the pace selected by manufacturer and battery specs. Lower amp takes time to charge, higher amp will charge fast but will reduce life.
Sent via MIUI-G2X
Click to expand...
Click to collapse
How does it even fit? The ports are totally different. Perhaps an adapter?
Sent from my LG-P999 using xda premium
DON'T DO IT!!!! your phone will suddenly become just like everyone else's and you won't be able to do anything about it! your technology will become dumbed down, and you will becomea victim of conformity!
HEED MY WARNING!!!
Don't worry, using that iPhone charger/adapter won't turn your Android phone into an iPhone.
The iPhone charger/adapter is a 5 volt USB adapter, it will work. The battery will charge normally, there's a charge regulation circuit in the phone and protection circuitry in the battery which will ensure that the battery won't be screwed. I use a variety of USB power adapters which range in their current rating which is the maximum current the device is capable of supplying at the rated voltage (although the cheap adapters' output voltage decreases as the current output (load current) increases. The LG power adapter I have is rated at 4.8 Volts and 1 Ampere output. I use that, a USB port on my computer which is rated at 5 Volts and 1/2 Ampere (500 ma), and other 5V power adapters. I also use a variety of micro USB cables some of which are just for supplying power, not data, and they work too.
Core Memory said:
Don't worry, using that iPhone charger/adapter won't turn your Android phone into an iPhone.
The iPhone charger/adapter is a 5 volt USB adapter, it will work. The battery will charge normally, there's a charge regulation circuit in the phone and protection circuitry in the battery which will ensure that the battery won't be screwed. I use a variety of USB power adapters which range in their current rating which is the maximum current the device is capable of supplying at the rated voltage (although the cheap adapters' output voltage decreases as the current output (load current) increases. The LG power adapter I have is rated at 4.8 Volts and 1 Ampere output. I use that, a USB port on my computer which is rated at 5 Volts and 1/2 Ampere (500 ma), and other 5V power adapters. I also use a variety of micro USB cables some of which are just for supplying power, not data, and they work too.
Click to expand...
Click to collapse
Good info.
Thanks
Sent from my LG-P999 using xda premium
thanks for the informative reply Core Memory.
didnt think using iphone charger will turn my android into iphone
so, bottom line - it is safe to use that charger.
Thanks!!
un.droid said:
thanks for the informative reply Core Memory.
didnt think using iphone charger will turn my android into iphone
so, bottom line - it is safe to use that charger.
Thanks!!
Click to expand...
Click to collapse
Yes, it's totally safe. I've got a service manual for an LG phone which is substantially the same as the G2X and Optimus 2X which shows the battery charge circuitry. That circuitry regulates battery charging. Here's some more info regarding the battery:
90% = 4.05V +/- 0.05V
60% = 3.83V ditto
30% = 3.72V ditto
10% = 3.64V ditto
OFF = 3.42V
The battery voltage decreases according to the load current (milliamps) over a period of time. The higher the load current during a specific period of time, the quicker the battery voltage decreases; that's why it is important to have everything except the cell radio and the operating system off when the phone is in standby. There will be some background processes, etc., which are necessary too. Bluetooth, GPS, and WiFi quickly drain the battery. Automatic updating should be turned off always. If you're not expecting any calls, turn the phone off. Setup your phone to reroute received phone calls to your home or work phone, if the call is important they will leave a message, then pick up the messages at your convenience. Use a ROM and kernel which are known to have good battery life.
ive been useing the iphone dock to charge my g2x and it works fine lol no issue
Hi all,
I have various chargers at home for the various pieces of kit we have.
My Asus Transformer tf101 has a charger which outputs at 15V, 1.2A
We have other chargers for phones & another tablet all with usb sockets on them.
An HTC outputs 5V, 1A
An Alcatel outputs 5V, 350mA
A Lenovo outputs 5V, 1.5A
Can anyone confirm my understanding about which charger to use and when, please?
I believe that if I use a charger with a LOWER voltage & amerage output than that delivered by the dedicated device charger, that it will NOT damage the device I charge with it - but it will probably take longer to charge. Is this correct?
So I shouldn't use my tf101 charger with anything other than my transformer tablet because it is 15v. But would it be OK to mix any of the other chargers around as they are all 5V? EG could I safely use the HTC charger on the Lenovo? Does the output amperage figure matter, or just the voltage?
Presumably I could use the 5V chargers on the tf101 - but it would take 3 times longer to charge? Could I use the Lenovo charger on the tf101 or would the higher amperage damage the transformer, even though the voltage is lower.
Advice please, helpful members
janner43 said:
I believe that if I use a charger with a LOWER voltage & amerage output than that delivered by the dedicated device charger, that it will NOT damage the device I charge with it - but it will probably take longer to charge. Is this correct?
Click to expand...
Click to collapse
This is my understanding: I believe it to be correct, but I may be wrong.
You must match voltages, if you use a charger with too low a voltage, it won't damage the device, but it won't work either. If it's too high, that would potentially damage the device and not work.
You need not match amperages (current) but in order for it to work correctly, you must use a charger greater than or equal to the rated current, eg., if the device wants 3A and you supply 5, this _should_ be OK, as the device only draws 3. But if it's _too_ high and you may exceed cabling tolerances, as the cables are only designed to handle current up to a certain amount, but I won't worry about this unless you're intending to supply currents >10A, say.
You can't charge a 15 volt device with 5 volts you could leave it charging for a million years and it would still only be 5 volts.
You can't charge a 5 volt device with 15 volts or you will cook the electronic components inside.
Another thing to remember the plugs used for different devices will be different sizes. The charging voltage's are usually direct current (DC) with a positive and a negative so you must make sure that the connections are correct.
As for the current rating's of the other chargers my experiance has showed me that isn't quite as important, as the current rating listed on the label is the maximum current that the power supply should have taken out of it.....
If you need to know more about basic electronics there is plenty of sources of information if you search Google.
Sent from my HTC Legend using XDA App
You should always use a charger with same volts of the stock one. The amps is relative, it will determine how fast it "delivers" the current, so the greater it is, the faster it charges...
With the advent of the S4, and its higher capacity battery, one could understand a higher charging current. However, I seem to have uncovered some findings that the charging system on the S4 is a bit more complex than first thought!
This is a bit techy, and assumes you have a basic amount of electrical knowledge, ie voltages, currents, resistance etc., but I'll try and keep it as simple as possible for anyone who may not!
To explain: The mains charger supplied with the S4 is a model number ETA-U90UWE, rated 5V @ 2A. However, the phone will ONLY charge at full current (which as I have measured so far, depending on what the phone regulates it to, typically sits in the region of 1.2 - 1.5A), when using the supplied charger (or possibly one of equal or higher current rating, depending on how it's configured internally), AND the supplied usb cable, OR any other usb cable, provided its shielding (the metal outer surface of the connectors) is connected at BOTH ends of the cable. Use a cable that doesn't have this shielding, and the charge current drops, regardless of whether there is plenty of current available or not. Use a different charger with an unshielded cable and the current drops even more, again regardless of whether it can supply plenty more current.
My assumption on this, is possibly an effort by Samsung to avoid the scenario of sticking 1.5 amps down a flimsy cheapo cable, the wires of which will likely be too thin to carry it.
After doing some probing around with a meter, I have managed to find a slight difference with the charger itself, compared to a generic one. In a generic one, the two data pins are usually just shorted together, which tells most phones that it's a mains charger rather than a USB port. On the Samsung one on the other hand, the pins appear to be shorted together, and also connected via resistors across the supply line (known as a potential divider), which holds these shorted data pins at a certain voltage. This is what tells the phone what sort of charger it's connected to.
Attached are a couple of diagrams to show the difference between the two chargers. There are in fact various setups of resistors that different manufacturers use to set the charging current, so it's quite easy to run into compatibility issues!
To make this a little less confusing I have done some preliminary experimenting, and I set out my results here.
For the test, I used combinations of 4 different usb style mains chargers: an apple iPhone one rated at 1A, an iPad one rated 2.4A, an HTC 1A one, and the genuine S4 one. With these I used two cables - the supplied Samsung S4 one (which is shielded), and a cheap generic one (which isn't). I started by measured the charging current directly with a meter, by using a very short usb breakout lead I've made, enabling me to interrupt the 5V line. However, I soon noticed that the use of any extension cables, even shielded, can lessen the chance of maintaining a good shielding connection, so I continued the exercise relying on the "galaxy charging current" app to get a reading.
Charger.................... Cable................ Current (A)
=====================================
HTC 1A.................Generic..................... 0.5
HTC 1A.................Samsung S4..............1.0
Apple 1A...............Generic......................0.5
Apple 1A...............Samsung S4..............1.0
Apple 2.4A............Generic......................0.6
Apple 2.4A............Samsung S4..............1.3
Samsung S4.........Generic...................... 0.8
Samsung S4.........Samsung S4...............1.3
So as you can see from these results, the original charger makes a difference, and the supplied cable (or a good quality shielded one) makes a further difference. If you have any further findings please feel free to add them here.
I can see that this is going to confuse some people, as it has me, as I'm sure some will inevitably try charging up their phone on generic chargers/leads at some point, with potentially long charging times resulting!
.
Very nice findings! Thanks for sharing them.
Not only what you say about longer charging time, but also discharging may occur (it has with me) while connected to the USB. I left my phone with USB tethering and it shut itself down after a couple of hours (it was low on battery already). I wanted to keep all the accessories in "new condition" in case I sell the phone in a few months, but I guess this justifies using the official charger and usb lead.
I hope someone can shed some light on the detection mechanism or the particular characteristics of the official cable so it can be replicated in generic ones.
From your findings, also Appe 2,4A charger has some control on the cable used, thanks.
Yes, but you won't be able to get more than about 0.75A out of it even with the samsung s4 cable.
You could try to add an extension cable to check if the charging system needs exclusively an original samsung cable from the charger to the phone.
Original samsung charger => extension cable male/female => original samsung cable => phone
PS: is there an app to check the charging current?
My experiments used an extension cable, that's the one I made into a breakout cable. So no it doesn't change by adding a cable.
There is an app, called galaxy charging current, which I tried also. In the 0.75A results above it showed a max permissible current of 1000mA, with the fully samsung setup it showed 1900mA. In the lower scenarios is showed up as 460mA. Other than that it doesn't tell you anything, it literally just shows you a max possible current, not the actual current it's drawing.
I've found out what the issue was, my generic cable was obviously a cheap one and wasn't shielded! I have edited my original post to re-explain.
Also I did a further test on a PC usb port - the Samsung cable allowed for 500mA, but the unshielded cheap one only allowed about 350mA, so (as pintycar found out), the phone actually carries on discharging in this case!
Interesting post.
I've been trying to mod a car charger so that the s4 draws more than 300mA so far unsucessful. I'm going to add in the 82K resistance and see what happens.
demusss said:
Interesting post.
I've been trying to mod a car charger so that the s4 draws more than 300mA so far unsucessful. I'm going to add in the 82K resistance and see what happens.
Click to expand...
Click to collapse
Hi,
Using a 5a digital bench power supply, I took a normal micro USB cable, cut it in two, added in the 82k resistors and tested.
Before: 450ma, after 1.73a
Then using a clamp meter I tested it with a 2amp Asus tablet charger - it varied between 1.48 and 1.61 amp.
I have since built a few more cables - one to use in my car (again 2 amp charger).
All in all, it works very effectively. Thanks for the initial research (saved me having to open my charger.)
BTW I suspect it is the charger where the resistors are, not the cable, otherwise the phone would try to pull 1.5a + from a laptop if you connected it.
Left my samsung cable at work so will test it tomorrow (if I remember)!
W.
Interesting. So basically for us laymen, you are telling us to use the original charger and cables to the extent possible ... right?
Can you clarify to me what an unshielded cable is? Maybe with a picture? I've got a blackberry's cable at work connected to my PC.
At home, I also have a cable and charger that I got with my Nexus S (I think this says Output 5.0V ~ 0.7A).
Would this be a problem or can I get by with these?
Thanks
I've been using the Samsung cable+charger+USB extension cable and charging the S4 usually takes about 4 hours, I'm going to try with just the Samsung cable next time and see if it makes any difference since people are saying that theirs can be fully charged within less than 3 hours.
Paparasee said:
Interesting. So basically for us laymen, you are telling us to use the original charger and cables to the extent possible ... right?
Can you clarify to me what an unshielded cable is? Maybe with a picture? I've got a blackberry's cable at work connected to my PC.
At home, I also have a cable and charger that I got with my Nexus S (I think this says Output 5.0V ~ 0.7A).
Would this be a problem or can I get by with these?
Thanks
Click to expand...
Click to collapse
Hi,
I believe (guess work here ) that only the original charger "needs" a shielded cable - could be checked by shorting the ground and shield on one side and see if it works at the higher current - if I am bored I may do it - it probably checks the shield and limits the current if it is not there (note I have not tested this so only going by the first posters findings).
BTW a shielded cable has a wire mesh around the 4 internal cables - this mesh avoids external interference messing with the signals. Can't see it affecting the charging though BUT shielded cables tend to have thicker internal cables so could be related to this.
I have it charging at 1.7a on an unshielded cable (thought he power strands are thicker than average) Shielding should only affect the data transfer speed, not the charging current.
If the Nexus S has only a 700mah charger then this will not be able to provide enough current for high speed charging and could easily burn out - nice smell, dead charger, not much else. therefore only use a normal unmodified usb cable (and it will charge at about 450mah).
W.
all this would eexplian why the charger that camewith my S2 dosen't appear to charge my phone fully over night...
For what it's worth I'm charging with a Note 1 charger...a thick shielded cable via the S3 docking station....and getting 900mah...
will get my original cable tonight and have a go tomorrow...
interesting read, my s4 lead and charger are still in the box and I'm using my nexus 10 ones phone charged from about 30% to full in just over 2. may have to change the old HTC £2 lead I've got connected to my works pc then, maybe why it's struggling to charge when playing music. guess this is one way to get people to buy more expensive cables
Very interesting read, thanks TS.
My original charger and cable set is still in the box; I've been using my Mom's old Galaxy Note charger.
I'll try the original cable + wall mount and see how fast it is compared to my current charger.
wmccann2 said:
Using a 5a digital bench power supply, I took a normal micro USB cable, cut it in two, added in the 82k resistors and tested.
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Can you show me your final cable with a pic? Thanks
After this thread I have stopped using my blackberry bold cable to charge s4 and of course the cheap one too.. thanks op!
Sent from my GT-I9500 using xda app-developers app
I'm not sure if shielded vs. unshielded is the difference - probably wire gauge is the difference.
For example, if you shop at Monoprice, you have two options for USB cables: 28 gauge cables, and 24/28 gauge cables.
For wire gauge, lower is larger - the 24/28 gauge cables have thicker wires for the + and GND lines. A pure 28 gauge cable is likely to drop voltage a bit at high currents, and my observations have been that most newer devices, ESPECIALLY Qualcomm-based ones, are VERY finicky when it comes to input voltage drops.
As to the charger itself:
Apple chargers are almost guaranteed not to charge at full current, as they don't conform at all to the USB battery charging standard. Some newer Android devices do have at least partial detection of Apple chargers, so they may charge at 1A if an Apple charger is detected (any Apple charge, even 2.1A ones).
It sounds like the included official charger is a tablet-compatible one. Samsung tablets expect D+ and D- to be held by the charger at 1.2 or 1.8 volts (I forget which). As a result, Samsung tablets will not charge from standard chargers (like an N7 charger), but standard devices (like an N7) will charge from Samsung tablet chargers.
Now, the question is: Does the GS4 *require* a Samsung tablet-style charger, or did Samsung just include a tablet-style charger because it's backwards-compatible with standard devices? (less part numbers to track in inventory).
A useful pair of points would be: Using the same cable, does the Samsung charger behave significantly different from a Nexus 7 charger?
wmccann2 said:
Hi,
Using a 5a digital bench power supply, I took a normal micro USB cable, cut it in two, added in the 82k resistors and tested.
Before: 450ma, after 1.73a
Then using a clamp meter I tested it with a 2amp Asus tablet charger - it varied between 1.48 and 1.61 amp.
I have since built a few more cables - one to use in my car (again 2 amp charger).
All in all, it works very effectively. Thanks for the initial research (saved me having to open my charger.)
BTW I suspect it is the charger where the resistors are, not the cable, otherwise the phone would try to pull 1.5a + from a laptop if you connected it.
Left my samsung cable at work so will test it tomorrow (if I remember)!
W.
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I missed this post on my first read-through: What happens if you just short D+ and D- when using the bench supply?