Flashback: USB-C, the one cable that rules them all

The battle of the smartphone’s wired connector is over and USB-C is the best way ahead. This multifunctional port can do nearly all the things – it may cost gadgets, switch information, deal with audio and video output, and even allow you to join equipment.

How did we get right here? Effectively, the European Union has been attempting for years to get electronics producers to choose a standard customary to keep away from the mess (and waste) that proprietary connectors create. Early on microUSB was the popular connector, however with the arrival of USB Kind C or USB-C for brief, the trade turned to the brand new customary.

And because of some EU rules that come into pressure on the finish of 2024, USB-C is actually necessary for all transportable digital gadgets (with some exceptions for smaller gadgets like smartwatches).

Flashback: USB-C, the one cable that rules them all

Most smartphone makers have readily adopted USB-C, simply as they did microUSB earlier than it. The one huge blocker is Apple, which nonetheless makes use of Lightning on its iPhones, AirPods, and EarPods — that is it, all the things else has moved to USB-C, together with the distant for the brand new Apple TV.

We expect Apple’s lineup is an effective illustration of why USB-C is so good. The lighting is primarily a USB 2.0 port. This implies gradual information switch when syncing recordsdata between an iPhone and a pc, or when transferring RAW pictures from a reminiscence card to an iPad.

Do you know there’s already a Lightning-based card reader that works at USB 3.0 speeds? So sooner transfers are potential, nevertheless it looks as if a tough feat and solely the iPad Professional helps it. Even then, Apple has by no means launched a video adapter that may transcend 1080p.

Lightning can also be restricted within the quantity of pressure it may carry. The charger for iPhones tops out at 30 watts, whereas the Apple USB-C charger for newer MacBooks can output 140 watts. Effectively, it isn’t fairly customary, nevertheless it’s not the utmost that USB-C can maintain.

Let’s attempt to hold issues organized and break down the primary features of USB-C one after the other.


USB began life as an information port. USB 1.0 and 1.1 are gradual and barely remembered canines now, and USB 2.0 remains to be very a lot alive. USB-C has a complete of 24 pins, 12 on all sides (OK, 22 pins, however let’s not get too slowed down within the particulars). Within the center is one D+/D pair, that is the info connection of a typical USB 2.0 cable and is necessary for USB-C. This ensures that each one cables may have a minimum of some connection.

USB Type C cable terminal.
USB Kind C cable terminal.

USB 3 has added an extra pair of cables for information switch – there are 4 extra pairs within the USB-C plug. Whereas USB 2 is restricted to 480Mbps, the additional tethering of the USB-C cable permits switch speeds of 10, 20, 40 and even 80Gbps.

Fast word: The USB-C connector is utilized by USB, after all, but in addition by Thunderbolt. This distinction is about to vanish as a result of USB 4 is predicated on Thunderbolt 3 and the brand new USB 4 model 2 is predicated on Thunderbolt 4.

One other fascinating utility is carrying PCI-Specific alerts – principally a wired model of the PCIe slots on a pc’s motherboard. This made it potential to attach exterior GPUs to laptops with a single cable.


One other widespread use for USB-C is for video output. DisplayPort might be the most typical use and USB-C has largely changed the large previous DP port. Most significantly, it isn’t information or video, it is information, video, and energy.

This enables one gadget to hook up with a hub that provides an ordinary HDMI port, a number of USB Kind A and Kind C ports, probably a card reader, audio and microphone jacks, and so forth. Get a full desktop expertise with a single cable connection.

Flashback: USB-C, the one cable that rules them all

That is very helpful for laptops, after all, however many smartphone makers provide desktop modes — Samsung’s DeX, Motorola’s Prepared For, and Huawei’s have them too. Even Apple has one, Stage Supervisor for the iPad Professional (which makes use of USB-C, of ​​course).

Different choices moreover DisplayPort, MHL, and HDMI adapters are additionally out there. A few of these are lively converters that convert from one customary to a different, however there are easy passive converters as properly.

My voice

We’ll point out the sound right here rapidly. USB can drive an exterior DAC you could join headphones to. Nevertheless, as with video, there’s additionally a destructive choice – audio adapter accent mode.

USB-C has a variety of pins to work with and some of them could be remapped onto the cables wanted for a typical TRRS jack, so a easy passive adapter can join a headset with a microphone. Notice that this can be a purely analog mode and that the digital circuits are separated to keep away from noise.


The fundamental USB customary has very low energy limits (500mAh for USB 2.0), although most producers do not comply with the usual to the letter, so 10W adapters are quite common.

In fact, producers need their merchandise to face out and quick charging is a method to try this, particularly now that smartphone batteries have a capability of 3-6000mAh. This led to a number of proprietary options reminiscent of Qualcomm’s Fast Cost and Oppo’s VOOC.

Nevertheless, the usual methodology is USB Energy Supply (USB-PD for brief). The preliminary model described a number of voltages and present ranges that may very well be supported – 2 amps at 5 volts, in addition to 3 amps or 5 amps at 12 volts or 20 volts. This gave Energy Supply a really wide selection from 10W to 100W.

Nevertheless, these fixed voltages require DC to DC conversion contained in the cellphone to make it extra appropriate for the lithium battery inside. USB-PD Revision 2 provided extra voltages – 9V and 15V – nevertheless it wasn’t sufficient.

Model 3 permits gadgets to speak to their chargers and request a selected voltage. It may possibly vary from 3.3V to 21V and could be precisely dialed in steps of 20mV. Chargers that assist this are marked “Programmable Energy Provide”. This fashion the charger is the one coping with the additional warmth, not the cellphone (lithium batteries do not prefer it when issues get sizzling).

Face fixed supply Programmable energy provide
fixed voltage mode 5 volts
9 volts
15 volts
20 volts
5V Prog (3.3V to five.9V)
9V Prog (3.3V to 11.0V)
15V Prog (3.3V to 16.0V)
20V PROG (3.3V to 21.0V)
Current Spherical (PDP/Voltage) to the closest 10mA RoundDown (PDP/Prog Voltage) to the closest 50mA
step measurement nobody 20 mv nominal
present restrict setting nobody Sure, nominal 50 mA steps
Rotating RDOs throughout operation No – not relevant Sure, it’s required to run PPS
Requires sturdy outlet design sure sure

The most recent USB-PD Prolonged Energy Vary customary provides extra fixed voltages – 28V, 36V, and 48V. This capped the brand new 240 watts of energy (48 volts at 5 amps), sufficient for even highly effective laptops (though telephones are already near the 240 watt restrict). There may be additionally a brand new adjustable voltage provide choice, which permits the gadget to steadily modify the voltage between 15V and 48V in 100mV steps.

Flashback: USB-C, the one cable that rules them all

Notice that for security causes these sturdy cables require a chip referred to as an “digital tag”. This chip signifies to the charger and to the cellphone (or laptop computer or no matter) that the cable is able to carrying the additional energy.

Some criticism

As a lot as we love USB-C, we won’t fake it is good. Our predominant grievance is that whereas there are such a lot of capabilities, not all gadgets and never all cables assist all the things. A variety of the options we talked about above are non-obligatory.

The worst a part of it’s that it may be very troublesome to know which gadgets and which cables assist what. USB-IF tries to easy issues out with new labels that clearly point out how a lot information and energy a given cable can carry.

This must also repair our different grievance, the naming system has grown to be an absolute beast. Do you know there isn’t a USB 3.0 anymore? USB 3.1 Gen 1 has been relaunched. However that is not there both, it is USB 3.2 Gen 1 now.

Issues are getting trickier with titles like USB 3.2 Gen 2×2. Ugh. Thankfully, all of that shall be changed by extra easy labels: USB 5Gbps, USB 10Gbps, USB 20Gbps, USB 40Gbps (and USB 80Gbps ought to be quickly). A lot better.

Flashback: USB-C, the one cable that rules them all

As for energy, there shall be two ranges – USB 60W and USB 240W. There shall be no 100-watt label for the reason that distinction between 100-watt cables and 240-watt cables appears sufficiently small that by the point the brand new labels go dwell, it will not make sense to promote 100-watt cables anymore.

Flashback: USB-C, the one cable that rules them all


USB-C was nice – we use it to cost telephones, laptops, headphones, razors, flashlights, and the rest that has a battery in it and suits in a backpack.

It has allowed us to create snug workplaces in our places of work with displays, keyboards, mice, and many others. all delivered to life with a single cable connection. And provided that the newest requirements permit it to hold much more information and energy than the unique specification, it is potential that USB-C hasn’t been developed but.

Will there be USB-D? Possibly, however not anytime quickly. Will the world drop cables and go wi-fi? In all probability not – it isn’t an environment friendly method to cost. It is not nice for information, as 2.4GHz Wi-Fi is already painfully crowded in residence buildings and 5GHz is crowding out too, prompting the Wi-Fi Alliance to maneuver to the 6GHz band.

For the foreseeable future, USB-C is the one cable that guidelines all of them.

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