Inside iPhone 8: new 29 watt Fast Charging like iPad Pro, using USB-PD

Posted:
in iPhone edited September 2017
Apple's new iPhone 8 supports new Qi wireless charging pads as a wireless convenience, but if you're in a hurry to recharge, you'll want to plug it in to take advantage of the significantly faster charge you can get using a standard 10 or 12 watt iPad adapter. New to iPhone 8 is an even quicker "Fast Charging" feature that uses the 29 watt USB-Power Delivery specification associated with USB-C and USB 3.1 to get you from zero to 50 percent in 30 minutes.




Out of the box, Apple continues to ship its latest iPhones with slow, square 5 watt USB chargers that are no faster than Qi wireless charging. The larger USB power adapters that ship with iPads (and sell separately) deliver 10 to 12 watts, and these can be used to safely recharge any iPhone significantly faster.

As with 12.9 inch and 10.5 inch iPad Pro models, the latest iPhone 8 and 8 Plus (and upcoming iPhone X) can make use of Apple's 29 watt USB-C MacBook power adapters (or the 61W or 87W USB-C power adapters that ship with new MacBook Pros) via Apple's USB-C to Lightning cable to charge at 29 watts (14.5 volts at 2 amps).

Note that this (rather expensive, $25) cable is designed specifically to accommodate the USB-PD 29 watt charging standard. Third party USB-C adapters may support USB-PD, but they aren't required to as part of the USB-C or USB 3 specifications. Similarly, third party cables with a USB-C port on one end and Lightning on the other don't necessarily support USB-PD, even if they do work fine for regular USB data sync and basic 10 to 12 watt charging.



Along the same lines, if you use a standard Lightning cable with a USB-C to USB-A adapter, even Apple's 29 watt charger will only support basic (non-PD) 12 watt charging (5.2 volts at 2.4 amps). This is not a conspiracy; the cables involved must all be designed to support the higher power distribution of USB-PD, not simply offer a physical chain of connections.

Also note that it's only the wall chargers that support USB-PD; anything you plug into your USB-C MacBook ports (even with a USB-C Lightning cable) will still charge at the same (non-PD) 10 watts as other modern Mac USB ports (5.2 volts at 2.1 amps).

That's also why you can't recharge a MacBook Pro daisy-chained to another MacBook via a USB-C cable; the new USB-C MacBooks use the same USB-PD specification to charge but can't deliver (or pass through) enough wattage to charge another USB-PD device.

Plugging in your iPhone into an older Mac or PC may deliver USB power even slower at around 2 watts (5v at 0.5 amps), which is the actual specification for USB 2.0. Starting with Macs from around 2011, Apple began providing additional (up to 10 watts) charging power than the spec allowed to devices that can handle it.

Whether you opt for the effortless Qi pad or a fast USB-PD cable, the total cost is going to be somewhere around $30-70, so it boils down to a choice between not having to poke in a cable and not having to wait for hours. It seems like Apple should at least include a 12 watt adapter with its premium priced iPhone 8 models, and should also make it a little easier for users to understand how fast their devices are charging and why (there's no indication in iOS that shows if you have achieved Fast Charging).

On a side note: Qualcomm Quick Charge is an proprietary protocol that is built into the Snapdragon SoCs used in many premium-priced Android phones, and is often cited as an advantage of Android reviews. It claims to support even faster charging than USB-PD, but it does this by modifying Vbus voltage levels and pin assignments of USB ports, creating new incompatibility issues between chargers and cables that "look like USB."

Google itself is strongly recommending its Android licensees against adopting Quick Charge rather than using the same USB-PD standard that Apple has used in its new MacBooks, iPad Pros and now iPhones.
watto_cobra

Comments

  • Reply 1 of 20
    I've been a big fan of Anker's 5-port desktop USB-A chargers and was planning on buying one of their USB-C ones, but their site says that it's not compatible with USB-C/Lightning cables even though they're capable of charging USB-C MacBooks. I'm puzzled over what the technical limitation is. 
    watto_cobra
  • Reply 2 of 20
    I would guess 29 watts vs 10 or 12 
  • Reply 3 of 20
    ao9newsao9news Posts: 1unconfirmed, member
    Hi, have you guys tested that it actually charges at 29W? There's a good reason no Android phone charges at anything close to that rate, especially for an extended period of time, even though there are a bunch of different standards on Android, none does more than about 20W. The Pixel XL "only" does 18W, and the smaller Pixel, 15W. And Android phones generally have larger batteries too.

    Just from a glance at the quoted rate of 50% in a half hour, doesn't square off with the measured rate of about 34% in the same time for an iPad pro 10.5, whose battery is over 4.4 times as large. (see http://forums.whirlpool.net.au/forum-replies.cfm?t=2641585). That measurement is consistent also with my experience with the iPad pro 12.9 charging at 29W measured with an USB-C meter.
    repressthisavon b7
  • Reply 4 of 20
    MplsPMplsP Posts: 690member
    "It seems like Apple should at least include a 12 watt adapter with its premium priced iPhone 8 models"

    Totally agree with this statement. When we're shelling out $700 and up for a premium phone (That Apple is already making a handsome profit on,) it seems like including a decent charging brick shouldn't be too much to ask.

    I'm just waiting for some Android device makers to adopt the Qualcom protocol with the modified USB standards - what a gawdawful mess that could turn out to be!
    watto_cobra
  • Reply 5 of 20
    How about some links and part numbers of the cables and power supplies. Keeping this all straight is becoming so complicated.

    My question is does any 12 watt USB-A charger work using the cable in the iPhone 8 box to give the faster charge.

    Also how long does it take to charge on 5W, 10W and the 29W with the special cable.
    Caffiend
  • Reply 6 of 20
    melgrossmelgross Posts: 31,170member
    This 30 minute 50% standard isn’t REALLY quick charging. It’s quicker charging. It’s the 15 minute to 50% charge Qualcomm charge that can potentially damage a battery, as the battery heats up more.
  • Reply 7 of 20
    melgrossmelgross Posts: 31,170member
    maestro64 said:
    How about some links and part numbers of the cables and power supplies. Keeping this all straight is becoming so complicated.

    My question is does any 12 watt USB-A charger work using the cable in the iPhone 8 box to give the faster charge.

    Also how long does it take to charge on 5W, 10W and the 29W with the special cable.
    Yes, it does. The 10-12 watt chargers are supported by all Apple made Lightning to USA A cables. They may not work properly with some third party cables, because some are not made properly, and can even be dangerous.

    in fact, buying an Apple branded charger or cable from Amazon, and likely a number of other retailers, probably will result in a fake Apple product. Somewhat over a year ago, Apple reported on a test they ran, and found that 90% of all Apple branded accessories on Amazon were FAKE.

    i only buy those directly from the Apple website, or an Apple store.
    pscooter63repressthispbruttowatto_cobra
  • Reply 8 of 20
    melgrossmelgross Posts: 31,170member
    ao9news said:
    Hi, have you guys tested that it actually charges at 29W? There's a good reason no Android phone charges at anything close to that rate, especially for an extended period of time, even though there are a bunch of different standards on Android, none does more than about 20W. The Pixel XL "only" does 18W, and the smaller Pixel, 15W. And Android phones generally have larger batteries too.

    Just from a glance at the quoted rate of 50% in a half hour, doesn't square off with the measured rate of about 34% in the same time for an iPad pro 10.5, whose battery is over 4.4 times as large. (see http://forums.whirlpool.net.au/forum-replies.cfm?t=2641585). That measurement is consistent also with my experience with the iPad pro 12.9 charging at 29W measured with an USB-C meter.
    They don’t charge at that rate. They charger faster than with the 12 watt charger though.
  • Reply 9 of 20
    Oppo's VOOC Charge is Innovation. 
  • Reply 10 of 20
    I think Apple needs to get in front of this question/issue -- before a third party starts to toast iPhones and blames it on Apple.
    watto_cobra
  • Reply 11 of 20
    avon b7avon b7 Posts: 2,785member
    MplsP said:
    "It seems like Apple should at least include a 12 watt adapter with its premium priced iPhone 8 models"

    Totally agree with this statement. When we're shelling out $700 and up for a premium phone (That Apple is already making a handsome profit on,) it seems like including a decent charging brick shouldn't be too much to ask.

    I'm just waiting for some Android device makers to adopt the Qualcom protocol with the modified USB standards - what a gawdawful mess that could turn out to be!
    It depends. Huawei uses its own batteries and charging technology on some phones but has several safety mechanisms built into the phones. You can plug in just about any charger and the phone will adapt to what is being delivered to it. If you can develop new technology and implement in a way that still provides users with the freedom to use alternative chargers, I think you get the best of both worlds.

    The Huawei charger will output a maximum of 22.5W if used with the Huawei cable which carries its own on board electronics so, just as mentioned in the article, to get absolute best results it is a requirement to use the proper cable. However, you are not required to use it (or the charger if you don't want to).

    https://huawei.trustedreviews.com/huawei-supercharge-super-smart-super-fast-super-cool-super-safe#UBcx7vJPej0mU2oJ.97



    Add me to those who think expensive premium phones should include fast chargers out of the box. Apple, Huawei, Samsung included. 
    edited September 2017 GeorgeBMac
  • Reply 12 of 20
    k2kwk2kw Posts: 1,378member
    MplsP said:
    "It seems like Apple should at least include a 12 watt adapter with its premium priced iPhone 8 models"

    Totally agree with this statement. When we're shelling out $700 and up for a premium phone (That Apple is already making a handsome profit on,) it seems like including a decent charging brick shouldn't be too much to ask.

    Not going to happen.   Apple didn't include the fast charger with the new iPadPros this year (As Niel Hughes pointed out).    So don't be surprised that all you get this year is the wireless charging via Qi.    Apple is probably already planning to drop the lightning port at some point in the future (3-5 years) when they think there will be enough chargers our there in the wild.   That's probably why the are still sticking with the slowest 5W out of the box charging so that when they do include the wireless charger instead it is same as 5W.
  • Reply 13 of 20
    k2kwk2kw Posts: 1,378member
    DED:
     Does the 29W USB-C fast charger  work with Apple's Smart Battery Case?   (I would be real impressed if the Fast Charger could simultaneously recharge the Smart Battery Case's Battery and the iPhone 8s battery at the same time.

    Will there be a Smart Battery Case for the iPhone 8 Plus or iPhone X?    Having lost power during hurricane IRMA for a few days I really would have liked to have had a battery case that could give me 2 days power on my iPhone 7Plus.   Would definitely upgrade.
  • Reply 14 of 20
    I think Apple needs to get in front of this question/issue -- before a third party starts to toast iPhones and blames it on Apple.
    Apple can publish their own specs/guidelines but can't force, test or monitor third party mfgs products, as that would be very time consuming and a legal nightmare.
  • Reply 15 of 20
    Are there any car chargers that support fast charge to the new iPhones ?
  • Reply 16 of 20
    k2kw said:
    DED:
     Does the 29W USB-C fast charger  work with Apple's Smart Battery Case?   (I would be real impressed if the Fast Charger could simultaneously recharge the Smart Battery Case's Battery and the iPhone 8s battery at the same time.

    Will there be a Smart Battery Case for the iPhone 8 Plus or iPhone X?    Having lost power during hurricane IRMA for a few days I really would have liked to have had a battery case that could give me 2 days power on my iPhone 7Plus.   Would definitely upgrade.
    Smart battery case?

    How about a battery that will charge any iPhone that you have or will have?

    I have this one. It can charge my iPhone 7 seven or more times, and I use a Lightning cable with an iPad (quicker) - or iPhone - power adapter to recharge the battery:

    https://www.amazon.com/gp/product/B0176HQ1O8/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
  • Reply 17 of 20
    realistic said:
    I think Apple needs to get in front of this question/issue -- before a third party starts to toast iPhones and blames it on Apple.
    Apple can publish their own specs/guidelines but can't force, test or monitor third party mfgs products, as that would be very time consuming and a legal nightmare.
    No, Apple can't force third parties to do anything.
    But that's a cop out:   There's a lot of ground between doing nothing versus dictating to the world.

    The world of charging just changed.  Right now Apple has chosen the do-nothing route in terms of leadership.   I am hoping that they show some leadership on this before their iPhones start getting turned into toast by improper charging.
  • Reply 18 of 20
    melgrossmelgross Posts: 31,170member
    realistic said:
    I think Apple needs to get in front of this question/issue -- before a third party starts to toast iPhones and blames it on Apple.
    Apple can publish their own specs/guidelines but can't force, test or monitor third party mfgs products, as that would be very time consuming and a legal nightmare.
    No, Apple can't force third parties to do anything.
    But that's a cop out:   There's a lot of ground between doing nothing versus dictating to the world.

    The world of charging just changed.  Right now Apple has chosen the do-nothing route in terms of leadership.   I am hoping that they show some leadership on this before their iPhones start getting turned into toast by improper charging.
    I guess you haven’t read about Apple’s own charging pad plans? The only one that can charge different devices at once. A device that “reads” where on the pad a device is, and just delivers power to that spot. There are some other advantages.

    Apple has delivered this significantly upgraded standard to the Qi group for incorporation the the Qi standard, to which this will be a major upgrade.

    so, according to you, what is “leadership” here? Apple coming up with a standard that’s completely theirs, so that no Apple devices can use the current Qi standard that’s being found almost everywhere, being the most used wireless standard? Would that be leadership?

    Or perhaps a real wireless standard that, so far, no one has been able to get to work well enough? Perhaps Apple has some “magic” they can apply here?
  • Reply 19 of 20
    I've been a big fan of Anker's 5-port desktop USB-A chargers and was planning on buying one of their USB-C ones, but their site says that it's not compatible with USB-C/Lightning cables even though they're capable of charging USB-C MacBooks. I'm puzzled over what the technical limitation is. 
    this one? https://www.anker.com/products/variant/PowerPort-5-Ports-USB-C-/A2052111

    I don't see where it says Lightning isn't supported.
  • Reply 20 of 20
    Did any editor of AI tested the charge before this post?

    After reading this post, I went to buy 1 29w and 1 87w with the new USB-PD cable, wanted to utilize the fast charge.

    What I found, 29w charges iPhone 8 at 0.7A with 14.5v = ~ 10w ; 87w charges at 1.35A with 8.8v = ~ 12w.

    This is tested with my iPhone 8 at 2% so it’s the fatest charge it could get.

    To compare, both chargers charge iPhone 7 at 1.6A with 5v = ~8w.

    I don’t see it anywhere near 29w. Did I do something wrong?

    Figures aside, the charges did get my iPhone 8 from 2% to 90ish% in an hr.
    Caffiend
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