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UPDATE: Ran the test again today, but using the included 5W 1amp charger. Took almost the same amount of time, only about 20-25 minutes longer. This time there was a big difference in time from when I plugged it in, and when it powered on finally (it must have been really dead.) Last time it went from flashing the "plug me in" graphic to powering on in about 2 minutes. This time it took almost 7 minutes to power on. Once on it was set with the screen at minimum brightness, but set on all the time so the video camera could capture the charge progress.

I also forgot I had a watts-up thing, and this time the charger was plugged into that also. The 1 amp charger pulled on average 4-4.2W for the bulk of the charge, then started to taper off at 70%, and was about 1.8-2W from 90-100%.

So it looks (to me at least) after testing that the iPhone SE doesn't support charging above 1amps. The 12W iPad Pro charger did charge it slightly faster, but we're talking 2 hours 14 minutes with that, vs 2 hours 40 minutes with the included smaller 1amp charger. Perhaps the 12W 2.4amp iPad Pro charger is a more efficient charger and can output the true max of 5W for the iPhone SE? (because it has some overhead room not being used? I dunno) I'm probably going to run this test one more time using the iPad Pro charger but this time plugged into the Watts-up thing and test that theory. I think it will feed the iPhone SE a solid 5W for the bulk of the charge (before the taper at 70%) vs the 4.2W the standard charger puts out. That small difference probably makes the iPad Pro charger charge up the iPhone SE a few minutes faster.

Interesting footnote though. For ***** and giggles (and because it was dead) I did the same test using my old iPhone 6 on the 12W iPad Pro charger, but this time also plugged into the watts-up as well. I should mention my iPhone 6 battery is terrible and is in no way representative of a normal battery. It's crap battery performance is part of why I bought a SE. According to iBackupBot it's cycle count is 478. <See attached screen shot>
Anyway the iPad Pro charger pulled 5.5-6.1W for the bulk of the charge, and also started to taper at about 70%, pulling 2.5-3W at the end to 100%. Dead to 100% charge in 1 hour 49 minutes.

/edit corrected my times after reviewing the time-lapse video of the charges.

Is it possible that the 5W charger doesn't utilize the full potential of the hardware? You yourself said that the maximum charge is 7.5W. So even the old 10W iPad charger will charge faster than the included adapter, because it pushes the hardware to its full potential.
 
Is it possible that the 5W charger doesn't utilize the full potential of the hardware? You yourself said that the maximum charge is 7.5W. So even the old 10W iPad charger will charge faster than the included adapter, because it pushes the hardware to its full potential.
That's what I plan to test next time the SE's battery dies (Probably tonight). I bet plugged into the 12W charger, the SE will pull a steady 5W, 1Amp. That slight increase over the smaller included charger (which averaged 4-4.2W) will probably equal the difference in charging times.

Either way, it's not pulling as much juice as the iPhone 6 does while charging, which was the real question we wanted answered.

/edit I also have the smaller 10W iPad mini charger, but for my test I'm sure it would provide the same numbers as the 12W version.
 
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OK final test complete:
Dead iPhone SE, charged up using the 12W 2.4amp iPad Pro charger. This time it took 2 hours 20 minutes to go from completely dead to 100%. It was plugged into the Watts-Up device and pulled 4.5-5W for most of the charge. Occasionally it would pop up briefly (for a second only here and there) into the 6-7W range, but I think that was only when it was doing some background tasks, as it almost always was steady flickering between 4.5-5.1W. (usually under 5W)
Taper barely started at 60%, which was almost exactly 1 hour in, but really started to drop off around 65-70%. At 99% it was barely pulling over 1W.

So not a huge change from the included 5W 1amp charger which averaged 4-4.2W on the Watts-up.

Final TL;DR: The iPhone SE does not charge significantly faster when using higher powered chargers, but there is a slight benefit to using them.
 
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OK final test complete:
Dead iPhone SE, charged up using the 12W 2.4amp iPad Pro charger. This time it took 2 hours 20 minutes to go from completely dead to 100%. It was plugged into the Watts-Up device and pulled 4.5-5W for most of the charge. Occasionally it would pop up briefly (for a second only here and there) into the 6-7W range, but I think that was only when it was doing some background tasks, as it almost always was steady flickering between 4.5-5.1W. (usually under 5W)
Taper barely started at 60%, which was almost exactly 1 hour in, but really started to drop off around 65-70%. At 99% it was barely pulling over 1W.

So not a huge change from the included 5W 1amp charger which averaged 4-4.2W on the Watts-up.

Final TL;DR: The iPhone SE does not charge significantly faster when using higher powered chargers, but there is a slight benefit to using them.

Sounds conclusive to me. Thanks for the scientific testing.
 
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Has anyone tried the 29W USB-C charger with the apple USB-C to lightning cable?
 
Has anyone tried the 29W USB-C charger with the apple USB-C to lightning cable?

If the SE doesn't use the 12W iPad Pro charger at full capacity I doubt 29W USB-C charger would be of any additional help.
 
If the SE doesn't use the 12W iPad Pro charger at full capacity I doubt 29W USB-C charger would be of any additional help.
I believe the usb-c to lightning cable has a different chip.
all my devices including the 5S charge much faster with the 29W and USB-C to lightning cable.
5S from dead to on in 6 minutes
 
I believe the usb-c to lightning cable has a different chip.
all my devices including the 5S charge much faster with the 29W and USB-C to lightning cable.
5S from dead to on in 6 minutes

It's not the charger brick that tells the phone how much power to take, the phone tells the charger what it wants and the charger delivers. If the phone only asks for 5W, that's all the charger is going to give it. Doesn't matter how much overhead (additional capacity) is available. The 12.9" iPad Pro will ask for the full amount that the 29W charger can provide. No other iDevice will though, it's the only one.
Testing Apple's 29W USB-C Power Adapter and iPad Pro ...
 
It's not the charger brick that tells the phone how much power to take, the phone tells the charger what it wants and the charger delivers. If the phone only asks for 5W, that's all the charger is going to give it. Doesn't matter how much overhead (additional capacity) is available. The 12.9" iPad Pro will ask for the full amount that the 29W charger can provide. No other iDevice will though, it's the only one.
Testing Apple's 29W USB-C Power Adapter and iPad Pro ...

Using a non-apple usb-c to lighting cable will not allow for any type of fast charging with any device. Using an apple cable all things change.
Using the Anker 60w usb-c charger and a apple usb-c to lightning will charge devices slightly faster but not as fast as an apple 29w and apple cable.

I have tried different devices, chargers and cable combinations.
One thing holds true. The Apple 29W charger and usb-c to lightning cable has charged my 5S, 6, 6+s, 12.9 ipp, ipad mini 4, ipad air 2 much faster than the 12W brick with an apple cable.
 
Using a non-apple usb-c to lighting cable will not allow for any type of fast charging with any device. Using an apple cable all things change.
Using the Anker 60w usb-c charger and a apple usb-c to lightning will charge devices slightly faster but not as fast as an apple 29w and apple cable.

I have tried different devices, chargers and cable combinations.
One thing holds true. The Apple 29W charger and usb-c to lightning cable has charged my 5S, 6, 6+s, 12.9 ipp, ipad mini 4, ipad air 2 much faster than the 12W brick with an apple cable.
Not sure how that would work for the 5s given that the phone itself limits how much charge it can take and the limit for 5s is lower than the other mentioned devices.
 
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OK final test complete:
Dead iPhone SE, charged up using the 12W 2.4amp iPad Pro charger. This time it took 2 hours 20 minutes to go from completely dead to 100%. It was plugged into the Watts-Up device and pulled 4.5-5W for most of the charge. Occasionally it would pop up briefly (for a second only here and there) into the 6-7W range, but I think that was only when it was doing some background tasks, as it almost always was steady flickering between 4.5-5.1W. (usually under 5W)
Taper barely started at 60%, which was almost exactly 1 hour in, but really started to drop off around 65-70%. At 99% it was barely pulling over 1W.

So not a huge change from the included 5W 1amp charger which averaged 4-4.2W on the Watts-up.

Final TL;DR: The iPhone SE does not charge significantly faster when using higher powered chargers, but there is a slight benefit to using them.

It's probably doing the same thing as the 6 and 6s which means that it has a fixed current it will charge the battery with, but it will use the additional headroom of a more powerful charger to power the device if necessary, which can have the effect of charging the battery faster. This is an improvement over the old 5/5s and previous design where the total current was fixed by what the battery accepts and if you were using the phone heavily (say for GPS navigation on a sunny day while streaming music in the car, or gaming) the charger could not keep pace with the current draw from the device. This no longer happens with the new models, even if the battery can't accept any more total current. (The Plus models DO allow additional current to go direct to the battery, making a noticeable difference in charge times).
 

Thicker gauge cables also help a bit, but not much. The phone still dictates how much to draw from the power source.
 
USB is 5v. so 1.5A @ 5V is 7.5W. The 2.4amp@5v (iPad charger) is 12W.

286W 5v would be 57.2 amps and would blow up your phone :eek:

57.2 amps would not blow up the phone. Even a million amps won't as the phone will only pull the amps that is required.
 
I was under the impression that prior to
iPhone 6 the phones wouldn't go above 1 Amp.
Some serious basic physics lesson is required, you've got 5 volts on the output, and 1.2 am, that's 6 watts, with 2.4 amps, that's 12 watts, where is this 100 watt or 200 watt non-sense come from?
[doublepost=1497639453][/doublepost]
57.2 amps would not blow up the phone. Even a million amps won't as the phone will only pull the amps that is required.
You clearly have no idea how electricity works, not to mention 50 amp, the little wires in our phone can barely handle 10 amp of current, 1 milllion amps would destroy the little iPhone into a piece of charcoal. For electricity and being dangerous, current is far more important than voltage. Your everyday static is thousands of volts, but dissipate minuscule of current for a tiny amount of time, you can easily survive that. At 50 amps, even at 5Volts, will give you a jolt you will not soon forget, if not kill in the process.
So in short, a current over 3 amp will most likely destroy your iphone's charging circuit, a 50 amp will light it on fire, and 1 million amps will reduce it into a pile of dust.
Power dissipation is calculated as current x voltage, and voltage is current x resistance (or impedance in complex phasor terms). So effectivly, power dissipated is current^2 x resistance, since your device's charging circuit's input resistance is relative fixed, the thing that really drives the power dissipation IS the current. A device design to use 1 mp that is subjected to 50 amps will receive 2500 x more power than it's designed to handle, you tell me how much it will be destroyed. Stay in school and learn some physics.
So lets come back, since the phone has a fixed input resistance, what's going to result in a 50 amp current, well if 5 volt input gives you 1 amp, then an input of 250 volts will give you ~ 50 amps, so subjecting the phone to a 250V DC input will put 50 amps into the phone and instantly destroy it. Well in theory, the control circuit in the front end of the iphone charging system should prevent the iphone from taking higher current IF the input voltage stays at 5v. It 's correct it's irrelevant what the max current the supply can handle, as long as the input voltage is regulated not to exceed 5 volts, but that's not what you said, you stated 50 amp will not destroy the phone, which is a laughable concept, because it clearly can and 100% will. But I bet you a supply capable of 50 amp (or a mllion amp as you so smartly mention) would have so much capacitance that it would inveritably change the impedance of the iphone's charging circuit, and will produce undesirable impact to the phone. That's why manufacturers recommend to use the included charger for your phone to charge your phone, because those little "wall wart" chargers are not all made the same.
[doublepost=1497641433][/doublepost]I think the answer to this question is depends on what you define as "fast charging". There marketing term "fast charging" in most android phone refer to the phone's charging chipset's capability to negotiate a higher input voltage from a compatible charger that will allow a higher input current at an higher input voltage which would dissipate more power at a considerable more rapid pace into the lithium cell. Lithium battery charge regulation is a current control process, which means the cells are charge controlled via a regulated current while the cell voltage varies depends on the amount of charge being put into the cell. A fast charging phone (use Samsung galaxy line as an example) mated with a "rapid charge" charger would actually negotiate an input charge voltage of 9 volts, this would allow the input current to be ~ 2x more than the 5 v input voltage, with a 2x input current, the power dissipation is then 2^2 =4 times the normal rate, so the battery is charge very fast. However, this charging current is only allowed when the lithium cell is relatively depleted (which mean the cell voltage is no where close to its rated max). That is why "fast charge" a phone works by allowing you to charge from 10 or 20% to 75% at a very fast rate. But to fully charge a lithium cell, the input current have to be carefully controlled otherwise the cell would leak and explode, that's why even with rapid charge the last 10-20% of the battery is charged no faster even with a "fast charger".
With iPhone, even up to iPhone 6s, full rapid charging (which is a capability directly support by Qualcom chipsets) is not available (since iPhones don't use Qualcomm chipsets). iPhones can't negotiate a higher initial input voltage like the high end android phones can. However, with newer iPhones, the maximum input current allowed by the charging circuit during the lower to middle charging curve (below 75% for instance) is increased because new iPhone are getting bigger batteries where the charging current limits would present a long charge time undesirable from a marketing perspective, that's why the new iPhone would charge faster when used with an iPad charger which could supply 2 amps at 5 volts vs. the 1amp at 5 volts of a regular iPhone charger.
HOWEVER, as a word of advice, one of the key ways to stress a lithium battery is to subject it to strong current while charging. A stronger current stresses the cells and reduce the charge cycle in the long run, that is also why many "rapid charging" android phones batteries tends to deteriorate faster than iPhones. Apple made a conscious decision to slow down iphone battery charging to extend the battery longevity in the long run. Feel free to "fast charge" our iphone, but do so knowing it may negatively impact the overall battery longevity.
My word of advice would be charge the iphone with the charge it comes with at the slower rate if you can afford the time, use a fast charger only when absolutely required. There is no free lunch.
Now the final drum roll, the iPhone SE, per my observation, absolutely the iPhone SE is capable of drawing more than 1 amp when charging if the charging adapter is capable of supplying that current (presumably because it uses similar innards as the iPhone 6s), however, there's little reason to push the little iPhone with more current considering how small the battery is, the benefit of getting the middle charge curve to proceed faster on such a small battery really doesn't offset the reduced longevity on the battery in the long run. It really doesn't take that long to charge the SE even with the regular iPhone charger.
So in a nutshell, iPhone SE will charge a bit faster with an iPad (or any 5 volt charger capable of supply 2 amp current), but it will do so at a bit of penalty to the long term battery longevity, now do what you need with full awareness of the physics behind the scene.
 
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Some serious basic physics lesson is required, you've got 5 volts on the output, and 1.2 am, that's 6 watts, with 2.4 amps, that's 12 watts, where is this 100 watt or 200 watt non-sense come from?
[doublepost=1497639453][/doublepost]
You clearly have no idea how electricity works, not to mention 50 amp, the little wires in our phone can barely handle 10 amp of current, 1 milllion amps would destroy the little iPhone into a piece of charcoal. For electricity and being dangerous, current is far more important than voltage. Your everyday static is thousands of volts, but dissipate minuscule of current for a tiny amount of time, you can easily survive that. At 50 amps, even at 5Volts, will give you a jolt you will not soon forget, if not kill in the process.
So in short, a current over 3 amp will most likely destroy your iphone's charging circuit, a 50 amp will light it on fire, and 1 million amps will reduce it into a pile of dust.
Power dissipation is calculated as current x voltage, and voltage is current x resistance (or impedance in complex phasor terms). So effectivly, power dissipated is current^2 x resistance, since your device's charging circuit's input resistance is relative fixed, the thing that really drives the power dissipation IS the current. A device design to use 1 mp that is subjected to 50 amps will receive 2500 x more power than it's designed to handle, you tell me how much it will be destroyed. Stay in school and learn some physics.
So lets come back, since the phone has a fixed input resistance, what's going to result in a 50 amp current, well if 5 volt input gives you 1 amp, then an input of 250 volts will give you ~ 50 amps, so subjecting the phone to a 250V DC input will put 50 amps into the phone and instantly destroy it. Well in theory, the control circuit in the front end of the iphone charging system should prevent the iphone from taking higher current IF the input voltage stays at 5v. It 's correct it's irrelevant what the max current the supply can handle, as long as the input voltage is regulated not to exceed 5 volts, but that's not what you said, you stated 50 amp will not destroy the phone, which is a laughable concept, because it clearly can and 100% will. But I bet you a supply capable of 50 amp (or a mllion amp as you so smartly mention) would have so much capacitance that it would inveritably change the impedance of the iphone's charging circuit, and will produce undesirable impact to the phone. That's why manufacturers recommend to use the included charger for your phone to charge your phone, because those little "wall wart" chargers are not all made the same.
[doublepost=1497641433][/doublepost]I think the answer to this question is depends on what you define as "fast charging". There marketing term "fast charging" in most android phone refer to the phone's charging chipset's capability to negotiate a higher input voltage from a compatible charger that will allow a higher input current at an higher input voltage which would dissipate more power at a considerable more rapid pace into the lithium cell. Lithium battery charge regulation is a current control process, which means the cells are charge controlled via a regulated current while the cell voltage varies depends on the amount of charge being put into the cell. A fast charging phone (use Samsung galaxy line as an example) mated with a "rapid charge" charger would actually negotiate an input charge voltage of 9 volts, this would allow the input current to be ~ 2x more than the 5 v input voltage, with a 2x input current, the power dissipation is then 2^2 =4 times the normal rate, so the battery is charge very fast. However, this charging current is only allowed when the lithium cell is relatively depleted (which mean the cell voltage is no where close to its rated max). That is why "fast charge" a phone works by allowing you to charge from 10 or 20% to 75% at a very fast rate. But to fully charge a lithium cell, the input current have to be carefully controlled otherwise the cell would leak and explode, that's why even with rapid charge the last 10-20% of the battery is charged no faster even with a "fast charger".
With iPhone, even up to iPhone 6s, full rapid charging (which is a capability directly support by Qualcom chipsets) is not available (since iPhones don't use Qualcomm chipsets). iPhones can't negotiate a higher initial input voltage like the high end android phones can. However, with newer iPhones, the maximum input current allowed by the charging circuit during the lower to middle charging curve (below 75% for instance) is increased because new iPhone are getting bigger batteries where the charging current limits would present a long charge time undesirable from a marketing perspective, that's why the new iPhone would charge faster when used with an iPad charger which could supply 2 amps at 5 volts vs. the 1amp at 5 volts of a regular iPhone charger.
HOWEVER, as a word of advice, one of the key ways to stress a lithium battery is to subject it to strong current while charging. A stronger current stresses the cells and reduce the charge cycle in the long run, that is also why many "rapid charging" android phones batteries tends to deteriorate faster than iPhones. Apple made a conscious decision to slow down iphone battery charging to extend the battery longevity in the long run. Feel free to "fast charge" our iphone, but do so knowing it may negatively impact the overall battery longevity.
My word of advice would be charge the iphone with the charge it comes with at the slower rate if you can afford the time, use a fast charger only when absolutely required. There is no free lunch.
Now the final drum roll, the iPhone SE, per my observation, absolutely the iPhone SE is capable of drawing more than 1 amp when charging if the charging adapter is capable of supplying that current (presumably because it uses similar innards as the iPhone 6s), however, there's little reason to push the little iPhone with more current considering how small the battery is, the benefit of getting the middle charge curve to proceed faster on such a small battery really doesn't offset the reduced longevity on the battery in the long run. It really doesn't take that long to charge the SE even with the regular iPhone charger.
So in a nutshell, iPhone SE will charge a bit faster with an iPad (or any 5 volt charger capable of supply 2 amp current), but it will do so at a bit of penalty to the long term battery longevity, now do what you need with full awareness of the physics behind the scene.

Long post...but in a nutshell, that is why I favor low amp charging and I've said this in many a thread.

I keep a higher amp powerblock on my desk that anybody can use to juice up their device, but I stay on the down-low. :)
 
I'm not sure why people are still debating this. I posted hard facts using actual real life testing over a year ago in the middle of this thread. The iPhone SE can not "fast charge".
 
I'm not sure why people are still debating this. I posted hard facts using actual real life testing over a year ago in the middle of this thread. The iPhone SE can not "fast charge".

I think your experiment was good and helpful, but others have a different interpretation of your results.

Your data was reported as:
"2 hours 14 minutes with [12W charger], vs 2 hours 40 minutes with the included smaller 1amp charger."
So that's 134 minutes vs. 160 minutes - about 20% faster using the iPad charger.

Taking this fact together with rigormortis' report that the iPhone SE draws in 1.5A (which is significantly more than the 1A charger can put out, it would seem to me that the iPhone SE can indeed charge faster (20% faster) with an iPad charger than with the standard charger it is sold with.

Since your conclusion from the results was that there is no benefit to using the iPad charger "the iPhone SE doesn't support charging above 1amps" the discussion continued.

You also provided other interesting facts such as "Last time [12W test] it went from flashing the "plug me in" graphic to powering on in about 2 minutes. This time [5W test] it took almost 7 minutes to power on" Seems to me like this is further evidence the SE is deriving power faster from the iPad charger while you dismissed it as "(it must have been really dead.)"

Again, great work on the testing - it's appreciated. We just have a different interpretation of the results.
 
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