Apple has now published an official support document that explains how to use the MagSafe Duo charger with iPhone 12 models and the Apple Watch. The power adapter was also mentioned.
The MagSafe Duo charger can charge an iPhone 12 – or alternatively AirPods – and an Apple Watch at the same time. However, the accessory is delivered without a power adapter. Apple itself recommends the brand new 20W adapter. The company has now published a support document published, which offers further details. It confirms that Apple's 29W USB-C adapter is not compatible with the MagSafe Duo. This is probably because the power adapter does not support the required 5V/3A or 9V/1.67A. If the adapter is connected to the MagSafe Duo, only one device - the iPhone or the Apple Watch - can be charged. Not both devices at the same time.
MagSafe Duo: 29W charger was replaced by 30W adapter in 2018
The 29W power adapter was replaced by a 30W version back in 2018. According to Apple, the 30W version is fully compatible with the MagSafe Duo. The support document also points out that the hinge area of the MagSafe Duo can become wrinkled over time if it is stored in the folded - i.e. closed - position. It states:
As with most soft materials, the accessory's cover may experience normal wear and tear over time. The hinge area of your MagSafe Duo Charger may develop creases over time if stored in the folded position. Leaving your MagSafe Duo Charger in the folded position in a very hot environment (such as inside a car on a hot day) may result in visible, deeper creases in this area. This does not affect the functional performance of the accessory.
Like the regular MagSafe charger, the MagSafe Duo is limited to a power output of up to 12W when used with the iPhone 12 mini. The rest of the article will repeat many of the details that Apple has already shared about MagSafe. (Image: Apple)