MagSafe charger wants to charge at full 15W speed but can only be used with Apple's 20W adapter

      Along with the iPhone 12 and 12 Pro, Apple also unveiled a new MagSafe charger that magnetically attaches to a ring on the back of the device and offers up to 15W of charging power, which is twice as fast as the maximum 7.5W Qi-based wireless charging speed.

　　Apple doesn’t include a power adapter with the MagSafe charger, requiring users to bring their own USB-C power adapter. Apple sells a new 20W power adapter, and it turns out that this seems to be the only power adapter currently capable of providing the full 15W charging power for the new MagSafe charger.

　　YouTube channel Zollotech tested several first- and third-party power adapters with an iPhone 12 Pro and a MagSafe charger, using a meter to measure actual power output. With the 20W power adapter provided by Apple, the MagSafe charger managed to reach 15W of power, but none of the other chargers he tested offered the same speed.

　　Apple's old 18W power adapter, which has been replaced by the 20W version, can charge an iPhone 12 Pro at up to 13W using a MagSafe charger, but the 96W power adapter and third-party power adapters that provide more than 20W cannot exceed 10W when used with a MagSafe Charger. Here are Zollo's test results.

　　Apple 20W power adapter --15W

　　Apple 18W Power Adapter -- 13W.

　　Apple 96W MacBook Pro Power Adapter - 10W

　　Anker 30W PowerPort Atom PD 1 = 7.5W to 10W.

　　Aukey 65W Power Adapter - 8W to 9W

　　Pixel 4/5 Charger - 7.5W to 9W.

　　Note 20 Super Charger - 6W to 7W.

　　To achieve maximum charging speeds with a MagSafe charger and an iPhone 12 or 12 Pro, you need Apple's 20W power adapter, and older power adapters won't work properly. Third-party companies will need to come out with new chargers that use the specific power profiles Apple uses to deliver the best power, and then third-party chargers will be able to deliver the full 15W of power from the MagSafe charger.

　　Zollo's testing also showed that Apple is using aggressive temperature control, so when the iPhone gets hot, charging power tends to stay below 10W.

　　Older iPhones, like the 11 Pro Max and 8 Plus, charge at around 5W using a MagSafe charger and Apple's 20W power adapter, so it's not worth buying a MagSafe charger to use with a non-iPhone 12.

　　IT Home learned that the same is true for Android phones. The MagSafe charger technically supports Qi-based charging and can be used with Android devices, but when used with an Android smartphone, the MagSafe charger outputs 1.5W, which is very slow and almost useless.