What is USB-C? It’s Not As Simple As You Think!

 Ah yes, USB Type-C, the new USB standard thatwill save us from constantly trying to put plug in a USB cable the right way. Most of you have heard of it by now if you’renot already using it, but you probably don’t know all the details. Like, what’s the difference between USB-Cand USB 3.1, or are all USB-C cables capable of the same speeds. Well that’s what we’re going to talk abouttoday, because even though all USB-C connectors look the same, there are a LOT of differenttypes of USB-C you should know about. And believe me it can get REALLY confusing,I literally did about 5 hours of research for this video, but I’ll try to make it easyto understand.

First of all, let’s start off very simple,what is USB-C. At it’s most basic level, USB-C just refers to this specific USB plug, plussome specifications for those cables’ wiring, and that’s it. So just saying “USB-C” only tells you aboutwhat the cable looks like, it doesn’t describe any specific speed, power capability, or supporteddata protocol. It was basically designed to be a more modern,future proof plug. Most notably, the plug has more pins so itcan do a lot more “stuff” which I’ll get to in a bit, AND the plug is reversable, so youcan’t plug it in the wrong way.

The joke with old USB cables was no matterhow many times you flipped it, you couldn’t plug it in until you looked at it. And by now you might be thinking, alright,so it’s just a plug. But, there are three main criteria that willbe very different that we can talk about. Those are data speed, power, and protcol,and those three differences are mainly what I’ll cover. Now quickly, before we get into that, I shouldpoint out that even though USB-C doesn’t describe any specific speeds or power capabilities,it does still have MINIMUM specifications. For example, all USB-C cables should supportat least 3 amps of electrical current, and 60 watts of power.

Also, because a USB-C cable is the same onboth sides, it must obviously be wired so it can send data and power both ways equally,called “dual role”. This is unlike previous USB cables, wherethe “host” side, such as your computer, typically had a USB-A connector, and the “device” hadsome other connector like MicroUSB or USB-B. So let’s get into the different possible speedsof a USB-C cable. You may already be familiar with USB 3.1,or “superspeed” USB, which supports up to 10 gigabit speeds. To be clear, USB-C is NOT any of those things. Again, USB-C is just the connector, whileUSB 3.1 is a data transfer standards.

Rather, a USB-C cable will use one or moreof those USB standards. That could be USB 2.0, 3.0, 3.1 Gen1, or 3.1Gen2. And depending on what USB speed rating ituses, it will have different maximum speed. That means that even though USB-C is the latestbrand new connector, you could still get one that only supports USB 2.0, and it will havethe same speed as a regular old USB 2.0 cable, just 480 megabits. Of course it may also support USB 3.1, butit’s not a guarantee. So you need to look at the labelling to seewhich speed it has. But one thing you can look for is if the cableis labelled as a “full featured” USB-C cable.

This term means that the cable supports thelatest USB 3.1 Gen 2 speeds of 10 gigabits per second, and is backwards compatible withUSB 2.0 as well. And that’s an actual term from the specificationdocuments, so you can’t just call a cable “full featured” if it doesn’t fulfill thatrequirement. Ok so those are the different speeds, nowlet’s talk about electrical power. As I mentioned before, any USB-C cable shouldhave a maximum current of at least 3 amps. Though there is one exception being a USB-Cto USB 2 Mini-B cable for some reason, which is 500mA, but let’s just forget about thatone.

Anyway, you may have also heard of USB “powerdelivery”, which allows for more electricity to be sent through USB, and more versatilecharging capabilities of up to 5 amps and 100 watts. This is much higher than the standard 3 amps60 watts. But again, not all USB-C cables, or devicesfor that matter, will have it. As you can imagine, if the USB-C cable doesn’thave power delivery, the most you can get is 3 Amps since that’s all the cable is ratedfor, even if the charger and device do it.

And by the way, it doesn’t matter what speedrating the cable is for it to have power delivery. Now if your cable, charger, and device dosupport power delivery though, it has some cool capabilities. Because you’ve got 100 watts to work with,you could charge much larger devices like a monitor without having to plug it into thewall, because all the data and power is through the USB-C cable. Also, power delivery does more than just sendpower, it also communicates information about connected devices.

Because if a cable or device doesn’t supportpower delivery, the power source will default to sending just 3A, but if it sees that itsupports power delivery, it needs to know more, like how much electricity to use. Also, power delivery can take advantage ofthe “dual role” ability of USB-C, so a port may be used either as a power input or output,or even switch between modes. This is why in the latest macs, you can chargethem by plugging the cable into any of the USB-C ports, and all those ports can alsobe used to power devices themselves. So make sure you know which of your devicesand cables support power delivery, so you can charge at maximum speed. Alright now the third topic I mentioned wasdifferent protocols that may use USB-C, called “Alternate Modes”.

And at the moment there are four, Displayport,thunderbolt, HDMI, and MHL. The first three you probably know, but MHLis used for connecting smartphones to TVs. If you’ve ever seen a microUSB to HDMI adapterfor a phone, it probably used MHL. And just like before, any given USB-C cablemay or may not support any of these protocols, AND of course these protocols won’t necessarilyuse USB-C. Obviously Displayport and HDMI have their own connectors you’ve seen, butthunderbolt 3 is actually going to use USB-C exclusively. But this is where it gets REALLY tricky. Because each “alternate mode” has differentcompatibilities which are pretty arbitrary.

Take Thunderbolt 3 for example. A thunderbolt 3 cable can be used for USB3.1, Displayport 1.2, and Thunderbolt obviously, as long as you have a Thunderbolt 3 port. And any thunderbolt 3 cable can also be usedfor USB 3.1, even if it’s not a thunderbolt port. BUT, there are actually two types of thunderbolt3 cable.

There’s an “active” cable which does 40 gigabits,and a passive cable which does 20 gigabit. Now say you have a native displayport jackon your computer, I just said that thunderbolt 3 supports displayport, so I should be ableto use a thunderbolt 3 cable right? Well maybe. You CAN use the passive thunderbolt cablewith up to native displayport 1.2, but you apparently CAN’T with an active cable, itmust be displayport over thunderbolt.

And if you can’t follow that, well just lookat this simple, easy to read table which tells you what cable types work with what modes! Sooo yea… Turns out USB-C isn’t going to be as universalas everyone thought. In fact, I think in some cases it will beeven MORE confusing. I mean, if you’re just looking for a cableto use for moving data over USB, basically any of the cables will work. Though even still, you’ll want to look atthe speed of it. But if you’re connecting a monitor or somethingthat uses USB-C, good luck. You’ll probably have to use one specific cable,that looks exactly the same as all the others except a little logo on the end.

At least now you can look at any cable andinstantly know what it’s for just by the connector, and you can be almost sure it will work. But with USB-C, I could totally see averagepeople trying to use a basic USB-C cable for a monitor, and having no idea why it won’twork. They should at least be color coded or something,like how USB 3 plugs are all blue. Now in general, I do think USB-C is a positivestep forward. I figure in MOST cases, it will just be usedfor regular USB, so it will be nice to know that if you buy some gadget, that you’ll beable to use it with everything else. I just wish they standardized the cables themselves.

At least then you’d just have to worry aboutif the devices you’re connecting are compatible, and not whether you’re using the right cablethat looks the same as all the others. And yea they will supposedly have logos fordifferent types, but that barely helps because they always use stupid names instead of givingthe specs. USB Full speed, USB Hi-speed, USB Super-Speed,USB super-speed plus! It’s like you have to memorize a chart ofwhat names correspond to what speeds.

Not to mention that “High speed” USB justmeans USB 2.0, which was released 17 years ago! In another 10 years they’ll be calling itUltra-Super-Duper-Mega-Max-Speed USB. Anyway enough rambling. Basically, just know that NOT all USB-C cablesare created equal, and I hope you learned all the different possible types you mightneed or come across.

Leave a Comment

Your email address will not be published. Required fields are marked *