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kat.hayes

macrumors 65816
Original poster
Oct 10, 2011
1,448
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I use a MacBook power supply with a USB c to lightning cable to fast charge my iPad 12.9. Will this work to fast charge the X?
 
Actually the 29W will be fastest, believe it or not. The 61W and 87W only provide 18W to iOS devices. Full discussion over in the iPad section. (H/T @masotime.)
but does iOS devices "support" fast charging right now? I don't think so. The new phones have this so I would assume it would be completely different?
I know the larger iPad charger charges my phone slightly faster but that doesn't mean the phone has fast charging.
 
but does iOS devices "support" fast charging right now? I don't think so. The new phones have this so I would assume it would be completely different?
I know the larger iPad charger charges my phone slightly faster but that doesn't mean the phone has fast charging.

Yes of course iOS devices support fast charging. This is absolutely true and verified across many sites for the iPad Pros 10.5" and 12.9". The iPhone is not the only iOS device. If you mean the other proprietary "fast charging" protocols developed by e.g. Qualcomm, probably not. However, that's for good reason - the world is unifying under USB-C Power Delivery and we should ignore the other standards for the sake of universal support.

@Brookzy is right however - a higher wattage charger does not automatically mean faster charging. Assuming that the "fast charge" depends on the USB-C PD protocol (very likely since that's the same way the iPad Pros charge), the charger itself must support the charging protocol that the iOS device also supports. For example, the 29W USB-C charger supports the 14.5V protocol @ 2A, whereas the 61W and 87W chargers only support 9V and then jumps straight to 20+ V (IIRC) bypassing 14.5V, so it only charges the iPad Pro @ 18W (9V x 2A) instead of the full 29W (14.5V x 2A).
 
Yes of course iOS devices support fast charging. This is absolutely true and verified across many sites for the iPad Pros 10.5" and 12.9". The iPhone is not the only iOS device. If you mean the other proprietary "fast charging" protocols developed by e.g. Qualcomm, probably not. However, that's for good reason - the world is unifying under USB-C Power Delivery and we should ignore the other standards for the sake of universal support.

@Brookzy is right however - a higher wattage charger does not automatically mean faster charging. Assuming that the "fast charge" depends on the USB-C PD protocol (very likely since that's the same way the iPad Pros charge), the charger itself must support the charging protocol that the iOS device also supports. For example, the 29W USB-C charger supports the 14.5V protocol @ 2A, whereas the 61W and 87W chargers only support 9V and then jumps straight to 20+ V (IIRC) bypassing 14.5V, so it only charges the iPad Pro @ 18W (9V x 2A) instead of the full 29W (14.5V x 2A).
and the new phones won't have different charging protocols?
 
and the new phones won't have different charging protocols?

Why would they? It's not out of the realm of possibility, but if Apple already has fast charging protocols for the iPad Pros, why would they change them for the iPhones?
[doublepost=1505289411][/doublepost]In any case over in the iPad forums we have done extensive analysis. See https://forums.macrumors.com/threads/87w-usb-c-charger-doesnt-charge-12-9-ipad-pro-29w.2015416/ and https://forums.macrumors.com/threads/29w-fast-charging-tests-and-3rd-party-adapters.2052414/

What might differ are the exact power delivery standards allowed. My best guess is that it will cap out at 9V/2A, so all the new iPhones will "fast charge" at 18W, but we need to have them and test them out to know for sure.
 
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no idea why they would make this post then https://www.macrumors.com/2017/09/12/iphone-x-iphone-8-fast-charge/
If they have had it for years and its not something new only for the new phones coming out. not talking iPads here.

The post is not inconsistent with what we currently know about fast charging. It already mentions both the 29W USB-C charger (and the 67W / 81W chargers) and the USB-C to lightning cable, which are all requirements for fast charging on the iPad Pro (the cable in particular is very important).

In all probability any USB-C PD compliant 3rd party charger will work just as well, allowing you to save some money. The nice part is that USB-C PD compliant 3rd party portable batteries will also fast charge. I've been using them a lot with my 12" MacBook and iPad Pros.
 
I think what x-evil-x was originally curious about is whether past iPhones now support fast charging.

They don't, as they don't have the required USB PD hardware.

Only iPhone 8, 8 Plus and X, and both the 2015 and 2017 iPad Pro 12,9" and iPad Pro 10,5" support it.
 
Ah ok now it makes sense. Because @Brookzy mentioned "only provide 18W to iOS devices", it could be implied that all current iOS devices support it, which is what @x-evil-x is questioning.

So the main point is that 87W doesn't guarantee the fastest charging, as proven by testing on the current iPad Pros. The rest is all a misunderstanding - the only current iOS devices now that support fast charging (> 12W) would be the 12.9" iPad Pros (1st and 2nd gen) and the 10.5" iPad Pro.

https://www.macrumors.com/2017/09/12/iphone-x-iphone-8-fast-charge/
87w highest end one should charge it fastest I'm assuming

Actually the 29W will be fastest, believe it or not. The 61W and 87W only provide 18W to iOS devices. Full discussion over in the iPad section. (H/T @masotime.)

but does iOS devices "support" fast charging right now? I don't think so. The new phones have this so I would assume it would be completely different?
I know the larger iPad charger charges my phone slightly faster but that doesn't mean the phone has fast charging.
 
The post is not inconsistent with what we currently know about fast charging. It already mentions both the 29W USB-C charger (and the 67W / 81W chargers) and the USB-C to lightning cable, which are all requirements for fast charging on the iPad Pro (the cable in particular is very important).

In all probability any USB-C PD compliant 3rd party charger will work just as well, allowing you to save some money. The nice part is that USB-C PD compliant 3rd party portable batteries will also fast charge. I've been using them a lot with my 12" MacBook and iPad Pros.

Yeah I'm wondering if this:

USB C Power Bank RAVPower 26800 PD Portable Charger 26800mAh(Faster Recharged in 4.5 Hours &USB-C Input, 30W Type-C Output)for Nintendo Switch, USB Type-C Laptops, 2016 MacBook Power Delivery Support https://www.amazon.com/dp/B01LRQDAEI/ref=cm_sw_r_cp_api_WGNUzb3ZE3G2Y

With a USB c to lightning cable would fast charge the iPhone 8.
 
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Would anyone be able to present a comparison of a full charge time for an iPhone with various chargers?

I found 5W vs 12W for iPhone 6 Plus (230 minutes vs 150 minutes), but no:
5W vs 29W
12W vw 29W
 
The 29W will not charge that phone faster than the 12W. It offers 5.2V x 2.4A, which is a bit over 12W. That's the same as the 12W charger.
 
Would anyone be able to present a comparison of a full charge time for an iPhone with various chargers?

I found 5W vs 12W for iPhone 6 Plus (230 minutes vs 150 minutes), but no:
5W vs 29W
12W vw 29W

There are no iPhones currently available that charge faster than 12W. Only the iPhone 8 and X do, and the actual charging speed is not known.

I just did some research, and assuming that the information given in this forum post is accurate, the 12W charger already charges an iPhone 7 up to 46% in 30 minutes, making the supposed fast charging of the iPhone 8/X very unremarkable.

In fact, given that we know the iPhone 8 has a 1821mAh battery, and assuming it's at 3.8V, that amounts to just 6.9Wh. Theoretically if it charges at 12W consistently for 30 minutes, that's 6Wh right there, which is 85% of the total capacity. We will need more information, but I suspect any "fast charging" is only really beneficial when your battery is low, as power regulation circuitry will greatly slow down the charge rate the closer you get to 100%. This is true even of the iPad Pros which have much larger batteries.
 
but does iOS devices "support" fast charging right now? I don't think so. The new phones have this so I would assume it would be completely different?
I know the larger iPad charger charges my phone slightly faster but that doesn't mean the phone has fast charging.
10.5/12.9 (v1 and v2) iPad Pro, and new iPhones (8/8+/X) are advertised as supporting fast charging

edit: @Puonti pointed out iPad Pro 9.7 is not advertised as supporting fast charging
 
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To triple clarify - the "fast charging" capability won't be available till the new software update comes out, right? In other words, when I have the shiny new iPhone 8 in my hand next Friday, regardless of additions I have to purchase, I won't be able to "fast charge" my phone.
 
There are no iPhones currently available that charge faster than 12W. Only the iPhone 8 and X do, and the actual charging speed is not known.

I just did some research, and assuming that the information given in this forum post is accurate, the 12W charger already charges an iPhone 7 up to 46% in 30 minutes, making the supposed fast charging of the iPhone 8/X very unremarkable.

In fact, given that we know the iPhone 8 has a 1821mAh battery, and assuming it's at 3.8V, that amounts to just 6.9Wh. Theoretically if it charges at 12W consistently for 30 minutes, that's 6Wh right there, which is 85% of the total capacity. We will need more information, but I suspect any "fast charging" is only really beneficial when your battery is low, as power regulation circuitry will greatly slow down the charge rate the closer you get to 100%. This is true even of the iPad Pros which have much larger batteries.

good info, sounds like Apple is just advertising something that's already been there somewhat. I always use at least a 2 amp charger to charge my iphone/ios devices. Don't know if there's that much difference.
 
To triple clarify - the "fast charging" capability won't be available till the new software update comes out, right? In other words, when I have the shiny new iPhone 8 in my hand next Friday, regardless of additions I have to purchase, I won't be able to "fast charge" my phone.
Not sure where you’re getting that from? iPhone 8 ships with iOS 11 and Apple is advertising fast charge support in 8/8+/X (assuming you buy the adapter and cable separately)
 
Not sure where you’re getting that from? iPhone 8 ships with iOS 11 and Apple is advertising fast charge support in 8/8+/X (assuming you buy the adapter and cable separately)

Outside of the cable & adapter - don't you still need to purchase an actual wireless device? Totally confused here...

My understanding is you need to have a wireless device to place your phone on top of to "fast charge" it. Apple did a terrible job at explaining how to work this - especially not having the products "in the box" to make it work.
 
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