Using Nexus 7 charger to charge mobile phones? - Nexus 7 Q&A, Help & Troubleshooting

Hi,
Nexus 7 charger ouputs 2A.
Is it safe and ok to use it to charge Galaxy Nexus, Nexus S, and HTC Desire?
I am thinking more in the long run, if it does not brake the phones.
Thanks

It should not hurt anything.My daughter charges her Droid 4 with my charger every day.

It'll charge it really slow since phone chargers are 1A. Everyone will have their opinion on this but my opinion is I wouldn't use a phone charger on the N7....it could over heat due to it charging slow. But I'm sure you'll hear others saying a slow charge is better so....
Sent from my Nexus 7 using xda premium

dirtyhamster73 said:
It'll charge it really slow since phone chargers are 1A. Everyone will have their opinion on this but my opinion is I wouldn't use a phone charger on the N7....it could over heat due to it charging slow. But I'm sure you'll hear others saying a slow charge is better so....
Sent from my Nexus 7 using xda premium
Click to expand...
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I was asking the other way around.
To use Nexus 7 to charge my phones. But the previous user just answered, thanks James.
When traveling, I want to carry just one charger for all my devices.
Sent from my Galaxy Nexus using xda premium

gogol said:
Hi,
Nexus 7 charger ouputs 2A.
Is it safe and ok to use it to charge Galaxy Nexus, Nexus S, and HTC Desire?
I am thinking more in the long run, if it does not brake the phones.
Thanks
Click to expand...
Click to collapse
Yup, it's fine, because a standard charger is, or used to be, 500 mAh, at 5 volts.
Some chargers are more mAh, like 700, and some are even 1 A.
If a charger is 2A, and your phone only draws 500 mAh, that is perfectly fine, because it's only drawing a quarter of what the charger can produce. In this case, the charger probably won't even get warm.

Neither my Sensation nor my wife's Sensation XL has died yet from using the Nexus charger
What mvmacd says is correct - just because the charger can supply 2A, it is the device that decides how much current it draws from the charger.

dirtyhamster73 said:
It'll charge it really slow since phone chargers are 1A. Everyone will have their opinion on this but my opinion is I wouldn't use a phone charger on the N7....it could over heat due to it charging slow. But I'm sure you'll hear others saying a slow charge is better so....
Sent from my Nexus 7 using xda premium
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I actually find the charger that came with my razr does the job fine and its rated at 850ma. Other lower power chargers i have are slow though.
I doubt a slow charge would lead to overheating or else connecting to a pc would cause this too.
I think for chargers its a case of trying them to see how well they work.
Sent from my Nexus 7 using Tapatalk 2

gbroon said:
I actually find the charger that came with my razr does the job fine and its rated at 850ma. Other lower power chargers i have are slow though.
I doubt a slow charge would lead to overheating or else connecting to a pc would cause this too.
I think for chargers its a case of trying them to see how well they work.
Sent from my Nexus 7 using Tapatalk 2
Click to expand...
Click to collapse
Science proves other than your opinion. A too-low or too high max voltage or amperage charger can and will lead to overheating and severe reduction on battery life and can destroy the adapter as well.

MrSchroeder said:
Science proves other than your opinion. A too-low or too high max voltage or amperage charger can and will lead to overheating and severe reduction on battery life and can destroy the adapter as well.
Click to expand...
Click to collapse
Care to explain why Google says you can charge your device with a 500 mAh charger [standard USB port]? ["with the screen off"]
Won't it severely reduce battery life and burn out the motherboard of the USB? Oh, really? Google just forgot about that part when they were writing the instruction manual?
:silly:

MrSchroeder said:
Science proves other than your opinion. A too-low or too high max voltage or amperage charger can and will lead to overheating and severe reduction on battery life and can destroy the adapter as well.
Click to expand...
Click to collapse
Science generally proves things with facts and figures. From a forum point of view, a link is your minimum effort here

MrSchroeder said:
Science proves other than your opinion. A too-low or too high max voltage or amperage charger can and will lead to overheating and severe reduction on battery life and can destroy the adapter as well.
Click to expand...
Click to collapse
Modern devices and chargers shouldn't have this problem because of built-in regulators. A smartphone won't try to draw more than it can handle and chargers won't try to supply more than they can handle (unless they're very cheap).

I have been N7 charger on phone with no problem so far. I wonder about the statement about the phone not drawing more than it needs though. I replaced the battery in my TB after 9 months due to low life and swelling. I'm pretty sure the swelling came from leaving the phone on a car charger all day, even after the battery was full. If my phone had the ability to stop taking the charge it didn't need, this wouldn't happen...
Sent from my Nexus 7 using xda premium

My opinion still stands....I don't trust using anything other than the charger that came with the device. 6th post down makes perfect sense to me.
http://forum.xda-developers.com/archive/index.php/t-1370215.html

Your battery was likely defective. My phone literally stays on the charger all day when I'm not out.

gogol said:
Hi,
Nexus 7 charger ouputs 2A.
Is it safe and ok to use it to charge Galaxy Nexus, Nexus S, and HTC Desire?
I am thinking more in the long run, if it does not brake the phones.
Thanks
Click to expand...
Click to collapse
If the phones also charge at 2A then you should be fine. If the phones charge at lower amps (say 1A or 1.5A) then I wouldn't recommend using it everyday as it may reduce the battery efficiency. If it's an emergency go ahead and use it.

There's no harm in using a higher current charger with a lower current phone because the charger is not what's actually charging the battery, it's the phone, and the phone will limit the charging current. You can confirm this with a multimeter. The charger can't force the phone to draw more current than it was designed for. This would be different if you were charging the battery directly with a dedicated charger because then the charger itself is directly controlling the charging current.

MrSchroeder said:
Science proves other than your opinion. A too-low or too high max voltage or amperage charger can and will lead to overheating and severe reduction on battery life and can destroy the adapter as well.
Click to expand...
Click to collapse
Nope, just nope.
Sincerely, an electrical engineering student.
Sent from my Nexus 7 using Tapatalk 2

Related

[Q] Charging with a 2.1 amp charger?

Do you think it would be safe to charge the evo with a 2.1 amp car charger? I found one on ebay that says its made for the iPad but I would love a faster charge on my epic.
In general, the slower you charge the battery, the longer it will last. The effect is pretty significant.
I don't know if that much current is safe.
http://www.batteryuniversity.com/parttwo-34.htm
Sent from my SPH-D700 using XDA App
It's more complicated than that. Just because the charger is able to provide 2.1A doesn't mean the phone will actually draw that much current.
The charge control circuitry is built into the phone. You are just providing a +5V rail as the charging power source via a standard USB connection. There is no charge control inherent in USB itself.
Sent from Samsung Vibrant
It will only pull as much as it needs. I use higher amp output chargers and it's not a problem. It will charge faster, regardless of what you use, if you turn the phone off.
jnadke said:
In general, the slower you charge the battery, the longer it will last.
Click to expand...
Click to collapse
Bingo.
Being an Aerospace Electrical Engineer I approve of this message.
jnadke said:
In general, the slower you charge the battery, the longer it will last. The effect is pretty significant.
I don't know if that much current is safe.
http://www.batteryuniversity.com/parttwo-34.htm
Sent from my SPH-D700 using XDA App
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Click to collapse
this is true, but the effect is not that significant, coming from using lithium packs in rc helicopers and cars, the battery will likely be obsolete before you kill it and the batteries aren't that expensive.
kerms said:
Do you think it would be safe to charge the evo with a 2.1 amp car charger? I found one on ebay that says its made for the iPad but I would love a faster charge on my epic.
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Click to collapse
do you have a link and is there a wall charger too? I run a remote desktop app and it destroys the battery, even with the 1 amp charger going the battery just gets lower and lower.
robl45 said:
do you have a link and is there a wall charger too? I run a remote desktop app and it destroys the battery, even with the 1 amp charger going the battery just gets lower and lower.
Click to expand...
Click to collapse
It could be due to the usb micro charging standards... Many chargers do not adhere to the standard, and this may cause some of the newer phones (droid X, galaxy S phones) not to charge at full power. Most older phones simply did not care, and would use all the amperage they could get their hands on.
Basically, if the D+ and D- pins of the USB cable are not shorted, then the device will draw minimal power from the +5v rail. It is probably drawing <500 mah, and could even be drawing as little as 100 mah from the charger.
Getting a proper 1A charger could fix this, but I'd like to test it out myself when I get the chance..
http://www.griffintechnology.com/products/powerduo-for-ipad
These work good. I use the ac one. Only thing is, like some have stated, even when charging when phone is on and using the phone, the battery will still go down. Maybe 2.2 will fix this or a patch.
I'm not going to debate fast vs slow charging. This isn't like debating what is the best charger for AA rechargeable nimh, fast or slow or charging method.

using an Apple/iPhone charger? ?

Is there anything wrong with using my iPod charger to charge my nexus 7?
It says 5v 1A, and it's an aftermarket white cube iPhone/iPod charger.
I plugged it in for a few seconds and it showed the charge icon.
Some people say it's better to charge slowly, and others say you might burn up the charger, so what's the deal here?
Also, does Apple have some kind of funny voltage thing? I seem to recall something like there's +3v or something on the data pin? Will that mess up something with long term use?
And while we're at it, what about the standard USB wall chargers, 500 mAh? How about those?
Yes there will be world war 3 and you will be taken to court.
Sent from my Nexus 7 using Tapatalk 2
u need 2a.
Your nexus will rma itself
Sent from my Nexus 7 using Tapatalk 2
seriously? I expected serious answers..
swisstourist said:
u need 2a.
Click to expand...
Click to collapse
but then why do they say you can charge it with a 500 mAh with the screen off?
xopher.hunter said:
Your nexus will rma itself
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Click to collapse
what do you mean, wiseguy?
The N7 charger is 2A, not 1A. So do not use it.
Sent from my Transformer TF101 using xda premium
just lou said:
The N7 charger is 2A, not 1A. So do not use it.
Sent from my Transformer TF101 using xda premium
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Click to collapse
so it won't just charge it slower? will it damage the charger or my N7?
mvmacd said:
so it won't just charge it slower? will it damage the charger or my N7?
Click to expand...
Click to collapse
Possibly all of the above could happen.
Sent from my Transformer TF101 using xda premium
just lou said:
Possibly all of the above could happen.
Sent from my Transformer TF101 using xda premium
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Click to collapse
what if it was 500 mAh?
even google says you can charge [with the screen off] at 500 mAh [standard phone charger, usb, laptop, etc]
so why would making that 1A ruin my device and the charger?
:victory:
mvmacd said:
what if it was 500 mAh?
even google says you can charge [with the screen off] at 500 mAh [standard phone charger, usb, laptop, etc]
so why would making that 1A ruin my device and the charger?
:victory:
Click to expand...
Click to collapse
no it will just charge slower. i dont know where people are getting their info that a lower amp charger can ruin your nexus. if the amp is too low it just wont charge. So when i nexus is plugged into my desktop to transfer files and charging it can get damaged?
ive been using 3 different chargers on my nexus 7 and they all work but at different rate. the lowest one is a 700mah motorola car charger that can still charge the tablet running maps and tethered to my phone. It charges very slowly though.
sometimes i plug it into my 1amp samsung charger to charge it overnight and would charge the nexus is about 4-5 hours. Im not sure if this is true but i read that using a slower charger is better on the battery. just be careful using cheap chinese chargers, those can ruin your device if you get a bad unit.
neotekz said:
no it will just charge slower. i dont know where people are getting their info that a lower amp charger can ruin your nexus. if the amp is too low it just wont charge. So when i nexus is plugged into my desktop to transfer files and charging it can get damaged?
ive been using 3 different chargers on my nexus 7 and they all work but at different rate. the lowest one is a 700mah motorola car charger that can still charge the tablet running maps and tethered to my phone. It charges very slowly though.
sometimes i plug it into my 1amp samsung charger to charge it overnight and would charge the nexus is about 4-5 hours. Im not sure if this is true but i read that using a slower charger is better on the battery. just be careful using cheap chinese chargers, those can ruin your device if you get a bad unit.
Click to expand...
Click to collapse
so how can it ruin my device? I can see how the charger can get burnt out if the 7 tries to pull too many amps from it...
and my charger is a chinese charger..
mvmacd said:
so how can it ruin my device? I can see how the charger can get burnt out if the 7 tries to pull too many amps from it...
and my charger is a chinese charger..
Click to expand...
Click to collapse
I'm not say all Chinese chargers are bad but just be careful with it. If your charger or tablet is not getting too hot while charging and stops when the battery is full then it's probably fine.
Will charge really slowly but will not damage. Why not using the n7 charger?
Sent from my Nexus 7 using Tapatalk 2
won't hurt it, I use many diffrent charges depending on where I am @ the time, mostly I use a cheap china dock that charges @ 1amp, a bit slow but works fine.
your only issue may be the scorn your n7 feels as an apple product revitalizes it
Sent from my HTC Vision using xda premium
Yeah, it'll charge really slow. There won't be any damage to the Nexus or the charger.
Sent from my Nexus 7 using Tapatalk 2

different charger amp levels

I recently bought the nexus 4 and have been having a blast with it. For a little while I lost the USB charger in my house, so I started using my iPad charger for it. Since the stock nexus 4 charger has an output of 1.2 amps 5v DC and the iPad charger has 2.0 amps 5v DC would prolonged use of the iPad charger possibly affect how long the battery last since it charges it faster then normal, or am I just being stupid and its fine to use the higher amperage charger?
There is a lot of threads explaining this but I'll explain the best I can higher amp equals quicker charge however gets the battery hotter so the battery life could be affected
Sent from my Nexus 4 using xda premium
It is the phone that decides how much current to "pull", not the charger that "pushes" it.
So it's fine to use a higher-rated charger.
Sent from my Nexus 4
steviewevie said:
It is the phone that decides how much current to "pull", not the charger that "pushes" it.
So it's fine to use a higher-rated charger.
Sent from my Nexus 4
Click to expand...
Click to collapse
This info is correct. You have nothing to worry about.
Unless you go stupidly over. Like 13 amps will probably overload and Fry the charging circuit.
But at 2 amps you will be fine
Sent from my Nexus 4 using xda app-developers app
Current is not pushed... it is drawn. You could have 20 Amps available (like a typical 120V outlet). Whatever current the device plugged into it needs it will draw... nothing more.
With that said, Apple chargers do not short pins 2 & 3 (data pins) of the USB connector. Instead, they put a resistive load across them to communicate the charger specs to the device. Nexus (and most OEM Android) chargers short these pins. Some android devices, Nexus 7 for example, sense the load on Apple chargers' data pins and assume it is a computer and drops the load to draw only 500 MA. I have not tested the Nexus 4, but would assume it behaves the same way as a Nexus 7.
Okay thanks guys. I did notice it was a little warmer, but i think that might have been from the emulator on that i was using. Just wanted to make sure i was killing the overall possible battery life.

Charge using different charger

Hey i just want to know it is safe to charge this phone using 5 V 0.7 A?
Because i see in the normal charger, the output rating is 5 V 1,2A.
I am currently using my previous samsung charger (5 V 0.7 A) to charge my nexus 4. It is safe or not to do this?
I dont mind for if the charger take more time to get my battery full anyway.
Thank you very much
Sent from my Nexus 4 using xda app-developers app
It should be fine but yeah, it is going to take significantly more time to charge your phone
Sent from my Nexus 4 using xda app-developers app
THEindian said:
It should be fine but yeah, it is going to take significantly more time to charge your phone
Sent from my Nexus 4 using xda app-developers app
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Click to collapse
So it is safe...
I dont like our charger because the cable itself it's too short.i need longer cable so i can do couple thing when my nexus is being charged.
Thx you for your information pal
Sent from my Nexus 4 using xda app-developers app
boenklon2 said:
So it is safe...
I dont like our charger because the cable itself it's too short.i need longer cable so i can do couple thing when my nexus is being charged.
Thx you for your information pal
Sent from my Nexus 4 using xda app-developers app
Click to expand...
Click to collapse
No problem. You'll start running into problems when you use a charger with higher Amps than what you phone charger puts out ie a tablet charger. Good luck!
THEindian said:
You'll start running into problems when you use a charger with higher Amps than what you phone charger puts out ie a tablet charger. Good luck!
Click to expand...
Click to collapse
A piece of electronic equipment only uses what it needs as far as electrical current is concerned. I am using a 2.5 Amp cigarette lighter charger with my Nexus 4. I could have used a 5V 100 Amp charger if I wanted, although it would have been tough trying to fit that giant connector into the micro usb port.
^ +1 You should have no problem using any charger that adheres to the USB spec and provides 5V reliably.
pjc123 said:
A piece of electronic equipment only uses what it needs as far as electrical current is concerned. I am using a 2.5 Amp cigarette lighter charger with my Nexus 4. I could have used a 5V 100 Amp charger if I wanted, although it would have been tough trying to fit that giant connector into the micro usb port.
Click to expand...
Click to collapse
Really? wouldn't it fry your battery as soon as you plug it in?
Sent from my Nexus 4 using Tapatalk 2
mynameisrio said:
Really? wouldn't it fry your battery as soon as you plug it in?
Sent from my Nexus 4 using Tapatalk 2
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Click to collapse
Nope, it would just insta charge your battery pretty much.. It probably would damn/fry itl; but only because the battery got hot.
Eagle1337 said:
Nope, it would just insta charge your battery pretty much.. It probably would damn/fry itl; but only because the battery got hot.
Click to expand...
Click to collapse
Even that is unlikely because the phone regulates how many amps to draw. The current allowed is regulated based on multiple factors including the battery temperature and the charge present in the battery.
raunaq360 said:
Even that is unlikely because the phone regulates how many amps to draw. The current allowed is regulated based on multiple factors including the battery temperature and the charge present in the battery.
Click to expand...
Click to collapse
Well the second scenario was if said bits failed
amps / volts
Think of volts as pressure, and amps as volume of flow.
Think of a conductor as the empty space of a pipe, the insulation as the pipe wall.
Higher volts needs stronger pipe (conductor insulation). The limited insulation in most modern electronics will burst if to much pressure (volts) is applied, causing a short and a fried device.
Higher amps requires a larger pipe (conductor) and will most always be limited by the size of the pipe, or the amount of volume consumed downstream.
If a charger puts out 100 amps and only .75 can fit through the pipe under a giving pressure (5 volts), then only .75 amps will be able to come out of the charger, without damaging anything.

Would charging with 'stronger' charger affect battery longevity?

I'm just wondering if using a different charger would affect the Z1's battery life?
I've seen the description on the original charger, and it's charge rate is 1.5mAh and with the phone's 3mAh battery almost 2 hours for it to charge. Now, my sister and dad have tablets and their chargers' charge rates are 2mAh.
Again the question is, would using these charges affect the life of the Z1's battery? Again, I'm very concerned because as you know, Z1's cannot be replaced conventionally.
Thanks for your feedbacks. Appreciate it.
Sent from my C6903 using xda app-developers app
I actually just bought the 2 Amp Samsung charger for that exact reason...takes too long to charge. I don't think there would be any issue.
Sent from my C6916 using Tapatalk 4
mrcrusha829 said:
I actually just bought the 2 Amp Samsung charger for that exact reason...takes too long to charge. I don't think there would be any issue.
Sent from my C6916 using Tapatalk 4
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Thanks for the quick reply dude, but any technical references or long-term observations that would prove this is okay?
Sent from my C6903 using xda app-developers app
FYI
Hi guys! You're totaly wrong. If you are use high-ampers chargers for your phones, you can destroy your battery or, at least, significantly reduce the battery life. I have some bad experience with motorola radio stations wich we use in some airport service groups. When we buy hi-ampers chargers for it we was happy by time of chargeing, but after half of year useing it we just throw out all accums, because it began to hold charge about hour or two only
After consulting with with motorolla support we have found that its strongly not reccomended to use charger with higher amperage then recomended by manufacturer.
As a result:
Positive - we have quick charging time
Negative - disastrous decline in the lifetime of the battery
romaha said:
Hi guys! You're totaly wrong. If you are use high-ampers chargers for your phones, you can destroy your battery or, at least, significantly reduce the battery life. I have some bad experience with motorola radio stations wich we use in some airport service groups. When we buy hi-ampers chargers for it we was happy by time of chargeing, but after half of year useing it we just throw out all accums, because it began to hold charge about hour or two only
After consulting with with motorolla support we have found that its strongly not reccomended to use charger with higher amperage then recomended by manufacturer.
As a result:
Positive - we have quick charging time
Negative - disastrous decline in the lifetime of the battery
Click to expand...
Click to collapse
tat is motorola. this is sony.
i also brought a samsung 2amp charger to charge my previous xperia v n current phone.
sony phone itself hav a circuit to regulate the input if it found charging amp way too high.
romaha said:
Hi guys! You're totaly wrong. If you are use high-ampers chargers for your phones, you can destroy your battery or, at least, significantly reduce the battery life. I have some bad experience with motorola radio stations wich we use in some airport service groups. When we buy hi-ampers chargers for it we was happy by time of chargeing, but after half of year useing it we just throw out all accums, because it began to hold charge about hour or two only
After consulting with with motorolla support we have found that its strongly not reccomended to use charger with higher amperage then recomended by manufacturer.
As a result:
Positive - we have quick charging time
Negative - disastrous decline in the lifetime of the battery
Click to expand...
Click to collapse
That's very unfortunate to hear dude, thanks for your input. I hope to not make the same mistakes again.
Sent from my C6903 using xda app-developers app
chunlianghere said:
tat is motorola. this is sony.
i also brought a samsung 2amp charger to charge my previous xperia v n current phone.
sony phone itself hav a circuit to regulate the input if it found charging amp way too high.
Click to expand...
Click to collapse
Thank you for your insight.
I have several questions though:
1) how long have you been using this 2amp charger? Was it continuous usage?
2) do you have any idea, or any exact figure on what "too high" means in numbers? That way we can all benefit if Sony phones could handle the extra "uhmp". And anyone who has a Z1 who can attest to this?
Sent from my C6903 using xda app-developers app
2amp isn't problem.
I'm using that charger (from my N7) and only thing I changed is cable - I'm using magnetic-microusb cable and that's great combo.
I'm charging Z1 from the day 1 (I bought Z1 in October 2013) and my battery is still perfect.
25-30hours with.5.5-6.5 h of screen time.
Sent from my C6903 using Tapatalk
The rated output of a charger is the maximum output, however it will only output what the phone takes in - in other words, if the phone only takes 1.5A, the charger will only output 1.5A even if it's capable of 2.1A. Using a higher ampere charger would only work if, say, the phone can take in 1.5A but the charger only outputs 1A, then using a 1.5A charger would boost charging times
funky0308 said:
2amp isn't problem.
I'm using that charger (from my N7) and only thing I changed is cable - I'm using magnetic-microusb cable and that's great combo.
I'm charging Z1 from the day 1 (I bought Z1 in October 2013) and my battery is still perfect.
25-30hours with.5.5-6.5 h of screen time.
Sent from my C6903 using Tapatalk
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Click to collapse
Hmmm, that looks promising, I also ordered a magnetic micro usb cable few weeks back. Thanks for your feedback dude.
Sent from my C6903 using xda app-developers app
pandaball said:
The rated output of a charger is the maximum output, however it will only output what the phone takes in - in other words, if the phone only takes 1.5A, the charger will only output 1.5A even if it's capable of 2.1A. Using a higher ampere charger would only work if, say, the phone can take in 1.5A but the charger only outputs 1A, then using a 1.5A charger would boost charging times
Click to expand...
Click to collapse
Yeah, that's what I also believe. But hey, then why do most gadgets heat up a little bit more when using a stronger charger? I'm not doubting the principles that you mentioned, but I need something tangible to look at: like an article from Sony for Z1 itself.
The other guy's experience and your comment here seems to be coinciding with each other, but You can never be too sure right?
But seriously, Thank you for your insight. I really appreciate it. That's what I like about the community here. Thanks man!
Sent from my C6903 using xda app-developers app
digiknowzone said:
Yeah, that's what I also believe. But hey, then why do most gadgets heat up a little bit more when using a stronger charger? I'm not doubting the principles that you mentioned, but I need something tangible to look at: like an article from Sony for Z1 itself.
The other guy's experience and your comment here seems to be coinciding with each other, but You can never be too sure right?
But seriously, Thank you for your insight. I really appreciate it. That's what I like about the community here. Thanks man!
Sent from my C6903 using xda app-developers app
Click to expand...
Click to collapse
Gadgets heat up more when using a stronger charger because of my second premise - that the phone is capable of taking in a higher amperage than the charger that it came with. I think such a scenario is more likely since manufacturers would find a balance between charging times and heat, since too much heat would permanently damage the phone's charging circuitry as well as shortening battery life, so they provide a charger that outputs a lower maximum than what the phone can take in.
I do not know of any documentation Sony might have on this, but this is more or less physics in action. I did find a couple of readings here and here, and the main snippets are as follows:
PopularMechanics said:
But the amperage rating is only a measure of the adapter's maximum capability—the actual amperage is determined by the load (i.e., the iPad or iPhone)
Click to expand...
Click to collapse
HowToGeek said:
If you connected the tablet’s charger to the smartphone, nothing would explode or catch fire. The smartphone likely won’t draw the maximum number of amps the charger can provide, but that should be fine. The smartphone may even charge a bit faster.
Click to expand...
Click to collapse

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