MagSafe 15W fast charging reportedly restricted to Apple 20W adapter

Posted:
in iPhone edited October 2020
New testing shows Apple's MagSafe charging puck does peak at 15W with iPhone 12, but only when paired with the company's 20W adapter.




The apparent restriction was discovered by Aaron Zollo of YouTube channel Zollotech. In a comprehensive evaluation of Apple's MagSafe device posted on Monday, Zollo found two Apple adapters -- a new standalone 20W USB-C device and the 18W unit that came with iPhone 11 Pro handsets -- achieved high rates of charge.

Measuring energy throughput with an inline digital meter revealed MagSafe hits the advertised 15W peak charging rate (up to 16W in the video) when paired with Apple's branded 20W adapter. Speeds drop to about 13W with the 18W adapter, and Zollo notes the system takes some time to ramp up to that level.

Older adapters and third-party models with high output ratings do not fare well in the test. Apple's own 96W MacBook Pro USB-C adapter eked out 10W with MagSafe, matching a high seen by Anker's PowerPort Atom PD1. Likewise, charging rates hovered between 6W and 9W when attached to Aukey's 65W adapter, Google's Pixel adapter and Samsung's Note 20 Ultra adapter.

It appears third-party devices will need to adopt a MagSafe-compatible power delivery (PD) profile to ensure fast, stable energy delivery when connected to iPhone 12 series devices.

As can be expected with any charging solution, temperature plays a significant role in potential throughput. Zollo found MagSafe significantly throttles speeds as temperatures rise, meaning actual rates are not a constant 15W even when using the 20W adapter. When heat rises, energy output decreases to protect sensitive hardware components and the battery itself. In some cases, this could prompt users to remove their iPhone from its case -- including Apple-branded MagSafe models -- to achieve maximum thermal efficiency.

Zollo also confirms older Qi-compatible iPhone models, like iPhone 8 Plus and iPhone 11 Pro Max, charge at about 5W with MagSafe. Apple previously said Qi devices would charge at 7.5W.

AppleInsider will be discussing USB-PD 3.0, MagSafe, and how they interact in the coming days.

Comments

  • Reply 1 of 20
    That seems odd. While the argument that a compatible PD profile is needed, Apple themselves state in writing that iPhone 12 is "Fast-charge capable: Up to 50% charge in around 30 minutes11 with 20W adapter or higher (sold separately)".
    The 'or higher' would indicate the their 30W, 61W or 96W would be just as capable. Has AI reached out to AAPL for comment?
    twokatmew
  • Reply 2 of 20
    AF_HittAF_Hitt Posts: 143member
    That seems odd. While the argument that a compatible PD profile is needed, Apple themselves state in writing that iPhone 12 is "Fast-charge capable: Up to 50% charge in around 30 minutes11 with 20W adapter or higher (sold separately)".
    The 'or higher' would indicate the their 30W, 61W or 96W would be just as capable. Has AI reached out to AAPL for comment?
    In Apple terms, Fast-charge and MagSafe are two completely different things. Fast-charge is using a USB-C to Lightning cable plugged directly into the phone using an Apple 20W adapter or any USB-C adapter that shipped with a MacBook. MagSafe, using the Apple-branded 20W USB-C adapter, will reach 15W, but this is slower than the maximum wattage when plugging a Lightning cable directly into the phone. It also generates more heat, which then kicks in the throttling, thus making the device not reach 15W charging at all times, only at peak, perfect temperature conditions.
    twokatmewJFC_PAGeorgeBMach4y3s
  • Reply 3 of 20
    “We took out the power adapter because we care about environmental waste”*







    *exceptions apply
    twokatmewmazda 3sentropysCloudTalkinmuthuk_vanalingam80s_Apple_GuyGeorgeBMackurai_kagechemengin1
  • Reply 4 of 20
    AF_Hitt said:
    That seems odd. While the argument that a compatible PD profile is needed, Apple themselves state in writing that iPhone 12 is "Fast-charge capable: Up to 50% charge in around 30 minutes11 with 20W adapter or higher (sold separately)".
    The 'or higher' would indicate the their 30W, 61W or 96W would be just as capable. Has AI reached out to AAPL for comment?
    In Apple terms, Fast-charge and MagSafe are two completely different things. Fast-charge is using a USB-C to Lightning cable plugged directly into the phone using an Apple 20W adapter or any USB-C adapter that shipped with a MacBook. MagSafe, using the Apple-branded 20W USB-C adapter, will reach 15W, but this is slower than the maximum wattage when plugging a Lightning cable directly into the phone. It also generates more heat, which then kicks in the throttling, thus making the device not reach 15W charging at all times, only at peak, perfect temperature conditions.
    Got it - and thanks.
    I still don't understand why higher chargers - particularly those by Apple - would not be able to emulate the 20W charger 15W capabilities for Magsafe charging (under 'ideal' conditions).
    That really would mean the 20W charger is 'special' in it's PD profile over even other, current Apple blocks?
    GeorgeBMacwatto_cobra
  • Reply 5 of 20
    mazda 3smazda 3s Posts: 1,613member
    I’ll stick with Lightning, thank you. Faster charging along with cheaper, longer cables available with less finicky restrictions about power output.  And I still have a problem with calling it “wireless” when you have a big, metal pod attached to the back of your phone, plugged into the wall. 

    To each his own. I’ll stick with my 18W Apple USB-C wall charger and 10-foot USB-C to lightning cable at my bedside. 
    raybowatto_cobrajony0
  • Reply 6 of 20
    entropysentropys Posts: 4,133member
    heli0s said:
    “We took out the power adapter because we care about environmental waste”*







    *exceptions apply
    Its amazing isn’t it. A supply chain cost saving and margin expanding measure just needs to be cloaked In virtue and idiots suck it up.
    If it wasn’t about money, the savings would have been passed on in lower prices for the iPhone. 
    muthuk_vanalingam80s_Apple_GuyGeorgeBMacMplsP
  • Reply 7 of 20
    lkrupplkrupp Posts: 10,557member
    entropys said:
    heli0s said:
    “We took out the power adapter because we care about environmental waste”*







    *exceptions apply
    Its amazing isn’t it. A supply chain cost saving and margin expanding measure just needs to be cloaked In virtue and idiots suck it up.
    If it wasn’t about money, the savings would have been passed on in lower prices for the iPhone. 
    Well, I guess you won’t be buying any more Apple gear then. Right? I mean you’re not one of the idiots, righjt?
    mwhitejdb8167watto_cobrajony0
  • Reply 8 of 20
    JFC_PAJFC_PA Posts: 930member
    Heat is why fast charging doesn’t thrill me. I’ve no interest in cooking my battery (unavoidable chemistry) for faster charging when I’ve got all night thankyouverymuch. 

    Cost savings were passed on I expect: 5G hardware etc. isn’t free. 
    edited October 2020 radarthekatjdb8167watto_cobrajony0
  • Reply 9 of 20
    Maybe restricting it is to avoid Note 7-type fires from overheating components.  I’ll stick to my Qi charger for overnight anyway as 5W seems safer for the battery than 18W for an overnight charge. Yes, I do like to start the day with 100%
    watto_cobra
  • Reply 10 of 20
    Opinion.  Reason for differing charging rates: Apple uses custom power delivery profiles... for every adapter they make.  Power adapters: https://support.apple.com/en-us/HT210133
    Every profile is different. None of the Macbook adapters match the 20W adapter's pd profile.   USB-C has 5 standard power delivery profiles.  Not really sure why Apple chooses not to use any of them.  

    The 5W adapter outputs 5V-1A
    The 10W adapter outputs 5.1V-2.1A
    The 12W adapter outputs 5.2V-2.4A
    The 18W adapter outputs 5V-3A or 9V-2A  (USB-C)
    The 20W adapter outputs 5V-3A or 9V-2.22A  (USB-C)  ← My guess: Match that pd profile or no soup for you.  In this instance, soup is 15W power delivery, not crab bisque. ;)

    mwhitePascalxxchiaGeorgeBMackurai_kagejony0
  • Reply 11 of 20
    Dunno ... special charging profile?

    Does it achieve higher charge rates with a MacBook?
    watto_cobra
  • Reply 12 of 20
    Apple is the undisputed master of slyly leading consumers to buy more Apple products and accessories.  All hail to Lord Humongous.  I don't care about fast charging as I would continue to use the standard cable and charge my iPhone overnight.  It's not because of the cost of the charger, but I'm satisfied with slower charging.  I'll admit Apple's 15W charging looks pretty lame when compared with some Android smartphones that have 65W charging.  It's rather impressive to see 1% of charge registering every ten seconds or so on an Android smartphone display.  Something like a 50% charge in 20 minutes is just bonkers.  And those companies actually provide a fast charger in the box.
    chemengin1
  • Reply 13 of 20
    "speeds drop to about 13W with the 18W adapter"

    Watts are not a unit of speed.
    fastasleepwatto_cobra
  • Reply 14 of 20
    tshapitshapi Posts: 369member
    mazda 3s said:
    I’ll stick with Lightning, thank you. Faster charging along with cheaper, longer cables available with less finicky restrictions about power output.  And I still have a problem with calling it “wireless” when you have a big, metal pod attached to the back of your phone, plugged into the wall. 

    To each his own. I’ll stick with my 18W Apple USB-C wall charger and 10-foot USB-C to lightning cable at my bedside. 
    It’s only a matter of time before Apple discontinued the lightning cable and we only have the option of wireless charging 
  • Reply 15 of 20
    GeorgeBMacGeorgeBMac Posts: 11,421member
    tshapi said:
    mazda 3s said:
    I’ll stick with Lightning, thank you. Faster charging along with cheaper, longer cables available with less finicky restrictions about power output.  And I still have a problem with calling it “wireless” when you have a big, metal pod attached to the back of your phone, plugged into the wall. 

    To each his own. I’ll stick with my 18W Apple USB-C wall charger and 10-foot USB-C to lightning cable at my bedside. 
    It’s only a matter of time before Apple discontinued the lightning cable and we only have the option of wireless charging 

    While that is likely true, don't forget that the lightening cable is mostly there for connecting to other devices -- like CarPlay and stereo equipment, not just for charging.   All of those connected devices would, in some way, need to be upgraded to wireless if Apple abandons the port in favor of wireless charging.
    radarthekatmazda 3s
  • Reply 16 of 20
    mazda 3smazda 3s Posts: 1,613member
    tshapi said:
    mazda 3s said:
    I’ll stick with Lightning, thank you. Faster charging along with cheaper, longer cables available with less finicky restrictions about power output.  And I still have a problem with calling it “wireless” when you have a big, metal pod attached to the back of your phone, plugged into the wall. 

    To each his own. I’ll stick with my 18W Apple USB-C wall charger and 10-foot USB-C to lightning cable at my bedside. 
    It’s only a matter of time before Apple discontinued the lightning cable and we only have the option of wireless charging 
    Once I get my iPhone 12 mini (128GB), I'm not upgrading for at least two years. I'll have 5G, and I'll have my small form-factor. By then, maybe all of this BS will be straightened out.

    While that is likely true, don't forget that the lightening cable is mostly there for connecting to other devices -- like CarPlay and stereo equipment, not just for charging.   All of those connected devices would, in some way, need to be upgraded to wireless if Apple abandons the port in favor of wireless charging.
    Bingo!
    curtis hannah
  • Reply 17 of 20
    And this raises the question even more of why not include an AC adapter with the Magsafe, as now it is more than clear it is only intended for the specific charger that they sale.
    GeorgeBMac
  • Reply 18 of 20
    Also interesting: the loss of power is only 4-5w. This will likely be a more rapid charging system than all prior included iphone chargers.
    watto_cobra
  • Reply 19 of 20
    MplsPMplsP Posts: 3,894member
    Also interesting: the loss of power is only 4-5w. This will likely be a more rapid charging system than all prior included iphone chargers.
    4-5 watts out of 20 is a 20-25% loss - that's a huge loss. 

    The article wasn't really clear how power was measured. Was it at the wall or at the device, and if it was at the device was it power at the puck or actual power delivered by the device? 
  • Reply 20 of 20
    MplsP said:
    Also interesting: the loss of power is only 4-5w. This will likely be a more rapid charging system than all prior included iphone chargers.
    4-5 watts out of 20 is a 20-25% loss - that's a huge loss. 

    The article wasn't really clear how power was measured. Was it at the wall or at the device, and if it was at the device was it power at the puck or actual power delivered by the device? 
    Did you even read the article or watch the YouTube video for reference? 
    watto_cobra
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