USB4 Specification Merges Thunderbolt 3 and USB With Transfer Speeds up to 40Gb/s

The USB4 specification for a new version of USB was today published by the USB Implementers Forum [PDF] giving us details on what to expect from the next-generation USB architecture following a preview back in March.

USB4 is a major update that "complements and builds upon" the current USB 3.2 2x2 (USB-C) and USB 2.0 architectures. According to the USB-IF, the USB4 architecture is based on Thunderbolt, doubling the maximum bandwidth of USB and allowing for multiple simultaneous data and display protocols.

usbccable
The USB-IF outlined key specifications of the USB4 architecture, such as 40Gb/s speeds (twice the current 20Gb/s maximum) and backwards compatibility with USB 3.2 and Thunderbolt 3.

  • Two-lane operation using existing USB Type-C cables and up to 40Gbps operation over 40Gbps certified cables
  • Multiple data and display protocols that efficiently share the maximum aggregate bandwidth
  • Backward compatibility with USB 3.2, USB 2.0 and Thunderbolt 3

USB4 will use the same USB-C connector design as USB 3, which means manufacturers will not need to introduce new USB4 ports into their devices.

Apple's newest Macs offer support for USB-C and Thunderbolt 3, which means most Mac users are already experiencing USB4 speeds when using Thunderbolt 3 cables and devices, but USB4 will make Thunderbolt-style speeds the new default and it will lower the cost of devices that use these faster transfer speeds.

USB Power Delivery will be required in devices built for USB4, which also means we can expect to see higher-powered chargers with multiple USB4 ports.

Though the USB4 specification is complete, it will still be some time before we can expect to see devices that take advantage of USB4. It typically takes at least a year for new products to come out following the finalization of a new specification, so it will be late 2020 or beyond before we begin seeing USB4 devices.

Popular Stories

iPhone SE 4 Vertical Camera Feature

iPhone SE 4 Production Will Reportedly Begin Ramping Up in October

Tuesday July 23, 2024 2:00 pm PDT by
Following nearly two years of rumors about a fourth-generation iPhone SE, The Information today reported that Apple suppliers are finally planning to begin ramping up mass production of the device in October of this year. If accurate, that timeframe would mean that the next iPhone SE would not be announced alongside the iPhone 16 series in September, as expected. Instead, the report...
iPhone 17 Plus Feature

iPhone 17 Lineup Specs Detail Display Upgrade and New High-End Model

Monday July 22, 2024 4:33 am PDT by
Key details about the overall specifications of the iPhone 17 lineup have been shared by the leaker known as "Ice Universe," clarifying several important aspects of next year's devices. Reports in recent months have converged in agreement that Apple will discontinue the "Plus" iPhone model in 2025 while introducing an all-new iPhone 17 "Slim" model as an even more high-end option sitting...
Generic iPhone 17 Feature With Full Width Dynamic Island

Kuo: Ultra-Thin iPhone 17 to Feature A19 Chip, Single Rear Camera, Semi-Titanium Frame, and More

Wednesday July 24, 2024 9:06 am PDT by
Apple supply chain analyst Ming-Chi Kuo today shared alleged specifications for a new ultra-thin iPhone 17 model rumored to launch next year. Kuo expects the device to be equipped with a 6.6-inch display with a current-size Dynamic Island, a standard A19 chip rather than an A19 Pro chip, a single rear camera, and an Apple-designed 5G chip. He also expects the device to have a...
iPhone 16 Pro Sizes Feature

iPhone 16 Series Is Less Than Two Months Away: Everything We Know

Thursday July 25, 2024 5:43 am PDT by
Apple typically releases its new iPhone series around mid-September, which means we are about two months out from the launch of the iPhone 16. Like the iPhone 15 series, this year's lineup is expected to stick with four models – iPhone 16, iPhone 16 Plus, iPhone 16 Pro, and iPhone 16 Pro Max – although there are plenty of design differences and new features to take into account. To bring ...
icloud private relay outage

iCloud Private Relay Experiencing Outage

Thursday July 25, 2024 3:18 pm PDT by
Apple’s iCloud Private Relay service is down for some users, according to Apple’s System Status page. Apple says that the iCloud Private Relay service may be slow or unavailable. The outage started at 2:34 p.m. Eastern Time, but it does not appear to be affecting all iCloud users. Some impacted users are unable to browse the web without turning iCloud Private Relay off, while others are...

Top Rated Comments

zedsdead Avatar
64 months ago
One cable to rule them all.

Now lets get USB-C on an iPhone.
Score: 49 Votes (Like | Disagree)
oneMadRssn Avatar
64 months ago
One cable to rule them all.

Now lets get USB-C on an iPhone.
Don't get me wrong, I like USB-C, but it is not the panacea everyone makes it out to be. There is not "one cable." There are a large number of different USB-C cables, all with different specs, speeds, etc.

Inexpensive USB-C charging cables are limited to USB2 speeds and most of them are limited to 30W of power. There are 60W and higher cables, but in 6ft lengths there are not as many options and it's far from easy to figure out what you're going to get. Some suppliers write the limits in terms of watts, some in terms of volts and amps. Most laymen have trouble figuring it all out.

And then there are the chargers... 18W, 30W, 60W, 90W, 100W, 5V, 12V, 18V, 2A, 3A. Chargers with two ports get even more confusing. While it's relatively easy math, I don't think having people doing Ohm's Law calculations in their heads when buying chargers in cables is user-friendly.

But I mentioned basic charging cables are super slow for data. If you want to use a USB-C cable for data, then it's even more confusing. Speeds vary depending on cable length and spec variant compatibility - a USB-C Gen 1 vs USB-C Gen 2 vs Thunderbolt 3; 1.5ft vs 3ft vs 6ft. Each combination will have a different max speed. It's all very difficult for most folks to keep straight.

Basically, USB is still a spaghetti of specs and limits, and this is just adding yet another layer. Just because the physical plug of Type C is nice, does not mean all the other USB problems are solved.
Score: 33 Votes (Like | Disagree)
Internet Enzyme Avatar
64 months ago
Congratulations Apple, you were four or five years early—you certainly earn that distinction. Too bad that the products in the meantime were entirely unflexible and annoying for anyone who wanted to conveniently use their laptop as a computer
Score: 16 Votes (Like | Disagree)
Spock Avatar
64 months ago
I don’t even have a Mac with USBC yet..
Score: 12 Votes (Like | Disagree)
tofagerl Avatar
64 months ago
Will USB4 then drop support for USB-A, B and B's little cousins mini and micro? Because if so, it's about time!
Score: 10 Votes (Like | Disagree)
zakarhino Avatar
64 months ago
Lightning is still the most robust port design I've ever come across for serious charging/data capabilities. I can plug my phone in every day multiple times a day for two years and the port will still be solid enough to dangle the iPhone from its charging cable no problem. Meanwhile the USB C ports on my MacBook are stupidly loose after just a couple months of use to the point where occasionally the charger would unplug itself if you move the laptop in a strange way.

I know this is controversial but I'd much rather keep a robust port on the iPhone (lightning) than a convenient yet fragile one (USB C).
Score: 7 Votes (Like | Disagree)