The Promise and Confusion of USB Type-CReading Time: 4 minutes
Okay, I’ll admit it. It’s not exactly the sexiest topic in the world.
But, when it comes to the practical, day-to-day existence with all of our modern devices, connectivity is an important story. When you survey the landscape of connectivity topics, it’s hard to ignore the impact various types of USB have had. Sure, the multiple new wireless standards tend to get a lot more attention. However, for most people, wired connections between devices are still an extremely common means of making things work and no wired connection is more ubiquitous than USB. (Except for power, but we’ll get to that in a second.)
The latest iteration of the USB connector is called Type-C, and while it was officially introduced in 2014, it’s really just starting to appear on the devices we can buy and use. Apple’s 2015 MacBook was among the first to support the new connector but it’s now showing up on all kinds of Windows PCs, smartphones, monitors, docking stations, storage peripherals and more. Like Apple’s Lightning connector, the USB Type-C connector is reversible, meaning you can plug it in in any orientation and it will work (and won’t get jammed in the wrong way).
USB Type-C is also associated with, though officially different from, USB version 3.1, which is currently the highest speed iteration of the standard. It supports transfer rates of 10 Gb/sec, a nearly 1,000x improvement over the 1996-era USB 1.0 spec, which topped out at 12 Mb/sec.
Equally important, USB Type-C supports several alternate modes, most notably the ability to carry up to 100W of power over the line, as well as the ability to drive up to two 4K displays at a 60Hz refresh rate. Best of all, it can do this simultaneously with data transfer, allowing a single connector to theoretically deliver power, data and video over a single line. Truly, this should be the one cable to rule them all.
As we all know, however, there’s often a big difference between theory and practice. The crux of the problem is that not all USB Type-C connectors support all of these different capabilities and, with one important exception, it’s almost impossible for an average person to figure out what a given USB Type-C equipped device supports without doing a good deal of research.
The key exception is for Thunderbolt 3.0, a technology originally developed by Intel. It’s a different interface standard than USB 3.1, but uses the same USB Type-C connectors. Thunderbolt 3.0 connectors (which, by the way, are different than previous versions of Thunderbolt—versions 1 and 2 used the same connectors as the mini-DisplayPort video standard) are marked by a lightning bolt next to the connector, making them easy for almost anyone to identify. To be clear however, they aren’t the same as the somewhat similarly shaped Lightning connectors used by Apple (which, ironically, don’t have a lightning bolt next to them). Confused? You’re not alone.
Arguably, Thunderbolt 3.0 is essentially a superset of USB 3.1, as it can carry full USB 3.1 signals at 10 Gb/sec, as well as PCIe 3.0, HDMI 2.0 or DisplayPort 1.2 video signals, 100W of power, and Thunderbolt data connections at up to 40 Gb/sec, all over a single USB Type-C connection. The only downside to Thunderbolt 3 is that it requires a dedicated Thunderbolt controller chip in any device that supports it, which adds cost. Also, full-bandwidth Thunderbolt 3 cables can be expensive, because they require active electronics inside them.
Standard USB Type-C, on the other hand, can be implemented by device makers a bit less expensively and full bandwidth cables, while also active, tend to be cheaper than Thunderbolt versions. However, along with this cost decrease comes the opportunity for confusion. Just because a device has USB Type-C connectors does not mean it supports power or any other alternate mode, such as support for video standards DisplayPort or MHL (used on some smartphones to drive larger displays). In fact, technically, it’s even possible to have USB Type-C ports that don’t support USB 3.1, although in reality, that’s highly unlikely to ever occur.
The real problem is there are no simple means of demarcation or labelling for different varieties of USB Type-C. One of the goals of the standard was to produce a much smaller connector that would fit on smaller devices—leaving little room for any type of icon.[pullquote]The real problem is there are no simple means of demarcation or labelling for different varieties of USB Type-C.”[/pullquote]
The other issue is, with the launch of USB Type-C, we’re seeing one of the first iterations of what I would call “virtualization” of the port. Until recently, each port had its own connector and carried its own type of signal. USB carried data to peripherals, Ethernet handled networking, video connectors such as HDMI and DisplayPort carried video, etc. Now the rise of multipurpose ports such as USB Type-C have broken that 1:1 correlation between ports and functions. While this consolidation is clearly an important technical step forward, it also points out the opportunity for confusion if user education and basic labelling techniques are overlooked.
On the bright side, this “virtualization” of ports will lead to a wide variety of the most useful docking stations and port replicators we’ve ever seen, particularly for notebook PCs, tablets, and even smartphones. You’ll be able to plug one cable into your device and get access to every single port you can imagine, as well as providing power back to the device. We’ll also start to see new types of peripherals, such as single cable monitors act as hubs to other devices, receiving power and video from the host device, while also enabling the connection of speakers, USB storage, and even a second daisy-chained monitor.
Eventually, most of these connections will likely become wireless but, given the need for power and the expected challenges around delivering wireless power to many devices, it’s clear variations on USB Type-C, particularly Thunderbolt 3.0 and later iterations, will be around for some time to come.
The proliferation of USB Type-C clearly marks the dawn of a great new era of connectivity for our devices, but it may require a bit of homework on your part to fully enjoy it.