USB-C Woes

Not many here remember the world before USB. Bulky connectors for "serial" and "parallel" cables. External power supplies for just about everything. USB changed all that, bringing together high speed data AND power. While HDMI failed to recognize this opportunity (there is no power on HDMI sockets, which limits heavily the usability of HDMI accessories), USB-PD (Power Delivery) over the Type-C connector has taken the cable unification to a new level.

I praised the potential of this new standard a number of times, at the same time highlighting the potential issues we have with it. The issues come down to the fact than not all USB-C ports nor cables are equal.

Ironically, Apple, who is considered a company promoting its own closed ecosystem is the best implementer and promoter of the standard connectivity technologies. Take the AirPods, which use Bluetooth and work with any phone (not just iPhones). Same with USB-C. They moved there first in MacBooks and now followed in iPads, which means iPhones will (finally) be USB-C too.

But USB-C seems to be challenging even for Apple. I recently discovered the genuine USB-C - to - HDMI multiport adapter is not capable of charging my 15" MacBook Pro. It probably limits the pass-through power to 60W, while the MBP needs almost 90W. See: Apple is not compatible with Apple.

Huawei, who has been playing a copycat with Apple, offers now the otherwise great Matebook with a bunch of USB-C ports. But neither has Thunderbolt 3 capabilities, and they are not created equal, either. The right-side USB-C port supports data transfer and DisplayPort connectivity, while the left-side port supports data transfer and charging.

Not long ago, in an attempt to streamline my accessories, I upgraded the Fornax astro tracking head with a USB-C input, capable of negotiating 12V (this is what the stepper motor inside needs) from the source. Paired it with a USB-C power bank, was almost ready to go, when I realized the power bank drops from 12V to 5V when a legacy USB-A cable is connected to it. Which ruined my idea of not having a separate 5V->12V step-up converter.

USB-C cables are another tale on their own. You need to be very careful when buying them and before going on a trip make sure they deliver what you expect. For data transfer, many of them work only at 2.0 speeds (0.48GBps vs 10GBps) and for power their mileage vary. The rule of thumb for Type-C Thunderbolt cables is that everything longer than 2ft should be optical, with converters built into each plug (the plugs are visibly larger).

USB IF (the Implementers Forum) recognizes the issues and have recently come up with the certification program. The certified cables have e-markers (small crypto chips) that can be verified upon connection. So long term things will definitely be simpler and the interoperability pitfalls will be rare or gone entirely. But for now, while extremely promising, the standard still requires careful navigation.