PSA: iPhone 8 Fast Charging Works With Third-Party USB-C Power Adapters That Support Power Delivery

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A recent support document on Apple's website confirms that you don't need one of Apple's USB-C power adapters to fast charge the latest iPhones.


Apple says the iPhone 8 and iPhone 8 Plus, and presumably the iPhone X, can be fast charged with any comparable third-party USB-C power adapter that supports the USB Power Delivery specification.

An official Lightning to USB-C cable is still needed, and it's not included with any iPhone. Apple charges $25 for a one meter cable, and $35 for a two meter cable, in the United States. There aren't any MFi-certified alternatives yet.

Apple's own USB-C power adapters that support USB-C Power Delivery include:
29W USB-C Power Adapter -- $49
61W USB-C Power Adapter -- $69
87W USB-C Power Adapter -- $79Aukey has a few cheaper third-party options available on Amazon:
29W USB-C Power Adapter -- $22.99
46W USB-C Power Adapter -- $39.99Fast charging enables the iPhone 8, iPhone 8 Plus, and iPhone X to charge to 50 percent battery life in just 30 minutes.

Disclaimer: This article is not affiliated with Aukey, but MacRumors is an affiliate partner with Amazon and may get paid if you click one of the above links and make a purchase.

Article Link: PSA: iPhone 8 Fast Charging Works With Third-Party USB-C Power Adapters That Support Power Delivery
 
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sixthdimension

macrumors newbie
Jul 20, 2010
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The first two links to third party adapters are AUKEY, not Anker.

Edit: Also, the last link for the Anker USB-C charger specifically states it does not support Apple's USB-C to Lightning cable. This has been confirmed by the reviewers.
 
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zhenya

macrumors 603
Jan 6, 2005
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Two of those 3rd party devices are Aukey rather than Anker.

But the last one posted - the Anker model, is an excellent little charger. I use one to charge my rMB and all my other usb-a devices.
 

alayal

macrumors member
Dec 8, 2015
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I have one power adapter in my amazon chart (UGREEN 29 W USB C) but I can't find a cable USB C - Lightning with USB - C PD, can anybody help?

thanks a lot in advance
 

Berzerker7

macrumors member
Jul 12, 2015
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This doesn't explain a question a lot of people have though: Will the 61 or 87W charge *faster* than the 29W? Is the highest power output the iPhone support 14.5V@2A or 9V@3A? The 29W Charger is the only one that has the specific 29W profile.
 

masotime

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Jun 24, 2012
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There's a much more in-depth discussion at https://forums.macrumors.com/threads/29w-fast-charging-tests-and-3rd-party-adapters.2052414/ - the iPad forum has known for some time that 3rd party USB-C PD chargers work instead of Apple's own.
[doublepost=1506366807][/doublepost]
This doesn't explain a question a lot of people have though: Will the 61 or 87W charge *faster* than the 29W? Is the highest power output the iPhone support 14.5V@2A or 9V@3A? The 29W Charger is the only one that has the specific 29W profile.
Refer to https://forums.macrumors.com/threads/fast-charging.2066638/page-2#post-25097840 - most likely it is 9V@2A i.e. 18W "fast charge".

Incidentally, both the 61W and 87W chargers charge the iPad Pros at 18W, not 29W like the 29W charger does.
 
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Berzerker7

macrumors member
Jul 12, 2015
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There's a much more in-depth discussion at https://forums.macrumors.com/threads/29w-fast-charging-tests-and-3rd-party-adapters.2052414/ - the iPad forum has known for some time that 3rd party USB-C PD chargers work instead of Apple's own.
[doublepost=1506366807][/doublepost]

Refer to https://forums.macrumors.com/threads/fast-charging.2066638/page-2#post-25097840 - most likely it is 9V@2A i.e. 18W "fast charge".

Incidentally, both the 61W and 87W chargers charge the iPad Pros at 18W, not 29W like the 29W charger does.
USB-PD uses a voltage regulator, though. So, your amperage should be consistently at 2-2.1A with a varying degree of voltage from 5 to 14.5 volts.

I'm assuming that the 61 and 87W chargers max out at 18W because they don't have the 14.5V@2A profile like the 29W charger has.
 
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masotime

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USB-PD uses a voltage regulator, though. So, your amperage should be consistently at 2-2.1A with a varying degree of voltage from 5 to 14.5 volts.

I'm assuming that the 61 and 87W chargers max out at 18W because they don't have the 14.5V@2A profile like the 29W charger has.
Hmmm... I haven't noticed the voltage varying in my tests, but the amperage does vary - this is using the Plugable USB-C meter, although that's testing with the iPad Pros.

I agree with you regarding the 61W and 87W chargers. In the link where I test the iPhone 8, I am using a RAVPower power bank that does charge the iPad Pros @ 30W (15V/2A), but for the iPhone 8 @ ~70% charge it does so at 9V / <2A. (as above, the voltage is fixed, but the current varies)
 

Joe Rossignol

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May 12, 2012
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The first two links to third party adapters are AUKEY, not Anker.

Edit: Also, the last link for the Anker USB-C charger specifically states it does not support Apple's USB-C to Lightning cable. This has been confirmed by the reviewers.
Two of those 3rd party devices are Aukey rather than Anker.

But the last one posted - the Anker model, is an excellent little charger. I use one to charge my rMB and all my other usb-a devices.
I was definitely confusing Aukey and Anker.

Also, I live in Canada, and was redirected to Amazon.ca, which didn't mention the Lightning incompatibility.

I've updated the article to address all of these issues.

Thanks!
 

Berzerker7

macrumors member
Jul 12, 2015
41
47
Hmmm... I haven't noticed the voltage varying in my tests, but the amperage does vary - this is using the Plugable USB-C meter, although that's testing with the iPad Pros.

I agree with you regarding the 61W and 87W chargers. In the link where I test the iPhone 8, I am using a RAVPower power bank that does charge the iPad Pros @ 30W (15V/2A), but for the iPhone 8 @ ~70% charge it does so at 9V / <2A. (as above, the voltage is fixed, but the current varies)
So it looks like USB-PD 1.2 removed fixed current with variable voltage in favor of a variable wattage at 4 voltage levels, 5, 9, 15, and 20V. This would imply they've moved for a current and voltage regulator mix that can charge at any variable wattage from 0.5W up to 100W. This complicates things further since we don't know what Apple is using and more testing would be required.

The 87W says "20.2V @ 4.3A (USB-PD)", which gives you ~87W. If the iPhone supports this, it should be able to charge at 87W. Same with the 61W charger denoting "20.3V @ 3A", giving you ~61W.
 

x-evil-x

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Jul 13, 2008
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So it looks like USB-PD 1.2 removed fixed current with variable voltage in favor of a variable wattage at 4 voltage levels, 5, 9, 15, and 20V. This would imply they've moved for a current and voltage regulator mix that can charge at any variable wattage from 0.5W up to 100W. This complicates things further since we don't know what Apple is using and more testing would be required.

The 87W says "20.2V @ 4.3A (USB-PD)", which gives you ~87W. If the iPhone supports this, it should be able to charge at 87W. Same with the 61W charger denoting "20.3V @ 3A", giving you ~61W.
Nobody has done tests yet with all the chargers? I don’t know if I want to take The iPad forums word on it without any iPhone testing.
I have a few 87w adapters sitting around
 

masotime

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Jun 24, 2012
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Nobody has done tests yet with all the chargers? I don’t know if I want to take The iPad forums word on it without any iPhone testing.
I have a few 87w adapters sitting around
Personally based on my limited testing which shows that the iPhone 8+ charges at 9V at 70% charge level, I think it's just going to charge at 18W maximum. It's unlikely to charge faster than an iPad Pro (29W) and given the small size of the battery, 18W or 9V/2A sounds more reasonable.
 
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Peter K.

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Nov 6, 2012
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Personally based on my limited testing which shows that the iPhone 8+ charges at 9V at 70% charge level, I think it's just going to charge at 18W maximum. It's unlikely to charge faster than an iPad Pro (29W) and given the small size of the battery, 18W or 9V/2A sounds more reasonable.
I agree. I once read a post from someone who claimed to be knowledgeable about battery science. He said that for each given size/capacity of a battery, there exists a sweet spot (range) of charging wattage ranging from X to Y percent.

The low-end, X, provides the slowest charging necessary to extend the life of the battery; the high end, Y, provides the maximum charging speed possible, without "damaging" the battery.
 
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PC97

macrumors newbie
Sep 25, 2017
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The first two links to third party adapters are AUKEY, not Anker.

Edit: Also, the last link for the Anker USB-C charger specifically states it does not support Apple's USB-C to Lightning cable. This has been confirmed by the reviewers.
Can anyone explain why it must be a USB C cable to Lightning and not the regular USB A? There are plenty of USB A Power Adapters that can draw 29W or more.
 

sixthdimension

macrumors newbie
Jul 20, 2010
27
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Indianapolis, IN
Can anyone explain why it must be a USB C cable to Lightning and not the regular USB A? There are plenty of USB A Power Adapters that can draw 29W or more.
Fast charge capable iOS devices are able to do so via USB-PD. Only USB-C output supports USB-PD, hence the required Apple USB-C to Lightning cable.
 
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oddiecz

macrumors member
Jul 7, 2010
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I keep seeing the same 50% in 30 minutes claim. How long does it take to fast charge from 0 to 100%? And is the reason 5W adapters are in the box that fast charging isn't good for the battery in the long-term?