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C DM

macrumors Sandy Bridge
Oct 17, 2011
51,392
19,458
I used to think this was going on too until I realized it was the cable I was using in the car vs home. At home I had a 6 foot cable and in the car a 3 foot. The 3ft was able to deliver a full 1 amp, but the 6 was limited to 2/3 of n amp due to it being low gauge wire. It was a cheap cable (about $1 when I bought 20 in bulk.)
As a result I was able to quick charge in the car but at home I never reached quick charge.

The phone limits to 1 amp draw. There is nothing special about it. No matter if you use a 10watt, 12watt, or 40watt, the phone is always going to self limit to 1 amp

Also note that a phone will only draw 1 amp and quick charge when the battery is below 80%. Above 80% there is a drop off to about .8 amps and reduces almost linear to 100% (about .4 at 90%)

I've done way way way too much testing with over 21 USB adapter/chargers and about 16 different brands/types of cables. Assuming the charger is iphone/iPad compatible it will always get identical performance on any iPhone. Depending on if you have a good or cheap cable, it could reduce that limit of current draw.
Stick with apple certified cables. if you're paying less than about $11 (depending on length) for a lightning cable, it's it's highly unlikely it's certified or decent quality.

All of my testing and investigation began because I found an inconsistency in charge performance and wanted to test it with real meters.

I have switched to using almost exclusively the Anker 40W 5-port charger http://www.ianker.com/support-c7-g345.html (they have a new 60W 6-port). For cables I'm using Monoprice or AmazonBasics.
For the car I'm using a TechNGo (sold at Walgreens) 2-port charger which delivers at least 3.2 amps. It charges two iPhones (1 amp each) at max rate. Their cables are also fine, but not too cheap. Still they are OK to get in a pinch. I've tested a bunch of car chargers and they all work well since little electronics is necessary because it's already DC current unlike a wall charger. So pretty much all, even 2 port, will deliver at least 1 amp per port unless they say otherwise.

Anyway, people will believe what they want but I'm 100% sure based on my extensive testing that an iPhone will never pull more than 1 amp for charging and all chargers that perform at 5 watts or more and a decent cable all perform identically.

Now when it comes to iPad, it's a different story. You're best off with a good high watt charger and you definitely need an Apple or certified cable to get over 2 amps (12 watts.) That's one reason I just use the Anker. It's versatile, 5 ports, and feeds anything as much as it needs.
An Apple 12W is $20 and I got several Ankers for $25 on sale, and they're 5 port. So I went with the value there.
The 6 and 6+ are not limited to 1 amp (unlike the previous models).
 

jeremiah239

macrumors 6502a
Nov 1, 2007
575
15
239 Area, FL
I used to think this was going on too until I realized it was the cable I was using in the car vs home. At home I had a 6 foot cable and in the car a 3 foot. The 3ft was able to deliver a full 1 amp, but the 6 was limited to 2/3 of n amp due to it being low gauge wire. It was a cheap cable (about $1 when I bought 20 in bulk.)
As a result I was able to quick charge in the car but at home I never reached quick charge.

The phone limits to 1 amp draw. There is nothing special about it. No matter if you use a 10watt, 12watt, or 40watt, the phone is always going to self limit to 1 amp

Also note that a phone will only draw 1 amp and quick charge when the battery is below 80%. Above 80% there is a drop off to about .8 amps and reduces almost linear to 100% (about .4 at 90%)

I've done way way way too much testing with over 21 USB adapter/chargers and about 16 different brands/types of cables. Assuming the charger is iphone/iPad compatible it will always get identical performance on any iPhone. Depending on if you have a good or cheap cable, it could reduce that limit of current draw.
Stick with apple certified cables. if you're paying less than about $11 (depending on length) for a lightning cable, it's it's highly unlikely it's certified or decent quality.

All of my testing and investigation began because I found an inconsistency in charge performance and wanted to test it with real meters.

I have switched to using almost exclusively the Anker 40W 5-port charger http://www.ianker.com/support-c7-g345.html (they have a new 60W 6-port). For cables I'm using Monoprice or AmazonBasics.
For the car I'm using a TechNGo (sold at Walgreens) 2-port charger which delivers at least 3.2 amps. It charges two iPhones (1 amp each) at max rate. Their cables are also fine, but not too cheap. Still they are OK to get in a pinch. I've tested a bunch of car chargers and they all work well since little electronics is necessary because it's already DC current unlike a wall charger. So pretty much all, even 2 port, will deliver at least 1 amp per port unless they say otherwise.

Anyway, people will believe what they want but I'm 100% sure based on my extensive testing that an iPhone will never pull more than 1 amp for charging and all chargers that perform at 5 watts or more and a decent cable all perform identically.

Now when it comes to iPad, it's a different story. You're best off with a good high watt charger and you definitely need an Apple or certified cable to get over 2 amps (12 watts.) That's one reason I just use the Anker. It's versatile, 5 ports, and feeds anything as much as it needs.
An Apple 12W is $20 and I got several Ankers for $25 on sale, and they're 5 port. So I went with the value there.


Was any of the testing done with the iPhone 6 or 6 Plus? Because just like the iPad the new iPhones pull 2.1A when available.

http://lifehacker.com/use-an-ipad-power-adapter-to-charge-your-iphone-6-faste-1637676153
 

Paco II

macrumors 68020
Sep 13, 2009
2,288
706
As mentioned, iPhone 6's can draw more than 1 amp and take advantage of the higher wattage chargers. But cable quality most definitely comes into play as well. If you ever see 'Not Charging' in the status bar, and you know the charger is good, that's a sure sign the cable isn't. And that's just at the extreme end.
 

Meltdownblitz

macrumors 65816
Jan 21, 2010
1,103
44
I have switched to using almost exclusively the Anker 40W 5-port charger http://www.ianker.com/support-c7-g345.html (they have a new 60W 6-port). For cables I'm using Monoprice or AmazonBasics.


You know what's good... Exactly what I stick to, best out there and with Monoprice's lifetime warranty it's almost unbeatable, I tested it the other day not by choice though obviously.

You get the most advanced charging speed for your device with anker wall chargers and best cables for cheap with lifetime warranty from monoprice!
 

RF9

macrumors regular
Jul 8, 2008
153
102
California
As mentioned, iPhone 6's can draw more than 1 amp and take advantage of the higher wattage chargers. But cable quality most definitely comes into play as well. If you ever see 'Not Charging' in the status bar, and you know the charger is good, that's a sure sign the cable isn't. And that's just at the extreme end.
My sincerest apologies for my inaccurate information. Serious screw up on my part. All of my testing was done pre-iPhone 6.

After reading the replies I tested on iPhone 6 and confirmed the great than 1Amp pull of an iPhone 6. Here were my findings with multiple chargers and cables:

Rapid Charging with screen off: 1.15 Amps
Rapid Charging screen on at max: 1.36 Amps
Rapid Charging screen on at low: 1.28 Amps
Max amp reading of 1.70 briefly when initially plugging in. Within 10 seconds it settles down to the 1.15-1.36 Amp range.
Running Waze with GPS on and screen at medium was 1.36 Amps.

It depends on what the phone is doing but the minimum pull is 1.15 and the maximum I read was 1.36, with the exception of 1.70 for a few seconds.

This was hardly an exhaustive test, but based on my findings any 12W does not charge faster than a 10W. I tested both and got the same.

I tested the following 4 USB AC chargers and cables with identical results:
Apple 10W, Apple 12W, Anker 40W (5 port), and PowerGen Dual USB 3.1A 15w Travel Wall Charger.
Monoprice 3ft, 6ft, and Apple iPad cables.

I did not test any automobile 12V chargers. I don't see why they'd give different results, though. I've never seen different results with iPad.

So I would recommend anything with a 2Amp (10 Watt) rating for fastest Charging. You'll see at least 20% faster charging. Even more if the phone is in use while charging.

I did not test an iPhone 6 Plus (I don't have one.) It has a larger battery (more cells?) so it's quite likely that it will pull more power for charging similar to an iPad.

I hope I cleared things up a bit. Again, sorry for my previous post not having updated info.
 

Trebuin

macrumors 65816
Jun 3, 2008
1,494
272
Central Cali
After reading some of these posts...I just have to to lighten the mood:

Try attaching it to a USB rigged with a lightning rod during a thunderstorm.

1) Does it charge faster?
2) Does it travel through time?

I looked at my phone charging and saw that you just can't predict how much CPU power is being used. The charging was all over the place. It starts from the max rate and then all the parts (CPU, WIFI, 3G, Blutooth...& so on) all suck what they need and then you're left with the charge rate.
 
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