A report today apparently answers an open question about MacBook Pro USB-C ports: whether or not they support the new USB PD 3.1 EPR standard needed for fast charging.
Unfortunately the news isn’t good. While there is a specification that supports the higher voltages needed, the new 16-inch MacBook Pro models don’t support it …
Background
We yesterday outlined the background to this.
When the USB-C standards were developed, there was a specific standard for charging, known as USB-C Power Delivery (PD). This allowed for power to be delivered via USB-C cables at up to 100W.
That was fine at the time, but with higher-powered laptops on the way, more power was needed. A new standard was developed to support power delivery of up to 240W, and Apple was instrumental in driving this. This new standard is known as USB PD 3.1 Extended Power Range (EPR). This delivers up to 48V at 5A, supporting anything up to 240W.
Apple’s new 16-inch MacBook Pro charger uses the new USB PD 3.1 EPR standard, and is – as far as I can see – the very first charger on the market to do so. Apple’s implementation is limited to 28v.
The 14-inch model isn’t affected as the charger is 96W, so below the 100W maximum.
MacBook Pro USB-C ports don’t support fast charging
A Reddit post by USB-C engineer Benson Leung yesterday noted that there isn’t yet a USB-C to USB-C cable that supports EPR, so fast charging is available only via the new MagSafe 3 port.
Apple was instrumental at proposing the 28V, 36V, and 48V new voltages levels to USB’s working groups, so it would make sense that they were planning on releasing the first implementation.
There are yet to be a C-to-C cable rated at EPR levels though. Apple’s using some proprietary cable to MagSafe.
However, Jason Snell says that the lack of a suitable cable isn’t the only issue.
On the 16-inch models—all of which come with a 140W adapter—you can only do ultra-fast charging via MagSafe. While there’s a new specification that allows for much higher power delivery levels over USB ports, the Thunderbolt 4/USB 4 ports on the MacBook Pro don’t support it. You can still charge via those ports, of course—just not at the ultra-fastest speed.
Snell doesn’t state a source for this info, but is unlikely to make such a definitive statement without hard facts.
The likely explanation is that the EPR standard is too new, so no suppliers have yet made USB-C ports that incorporate it – or, at least, not in the volumes Apple needs. Some even expressed surprise that Apple had managed to include it in the new MagSafe port. The latter fact is explained by the fact that the company had an inside track on the development of the standard, so was able to create a compatible proprietary cable.
It’s not a huge deal, as the machine comes with the MagSafe cable, so anyone wanting fast charging can use that. It would have been a nice-to-have, though.
