On September 1st of this year, the USB promotion organization announced the new USB 4.0 Version 2.0 (USB 4.0 Second Edition) specification, which will increase the USB type-C cable and connector speed to 80Gbps. The specific specification information will not be released until the USB Developer Conference in Seattle and Seoul ends in November this year, but this announcement has already revealed a lot of expected intelligence.

Jumping from 40Gbps to 80Gbps

The second version of USB 4.0 will become one of the fastest interface standards on the market, even surpassing Thunderbolt 4 and USB 4.0's maximum speed of 40Gbps, reaching a terrifying 80Gbps. In terms of protocol tunnel support, USB-IF indicates that the new version of USB 4.0 will support higher performance USB 3.2 as well as the new versions of DisplayPort and PCIe. The first version of USB 4.0 already supports USB 3.2 at 20Gbps (optional speed), and it seems that this version of the specification will bring USB 3.2's speed to new heights.

The second version of USB 4.0, like all previous USB standards, has achieved excellent backward compatibility as always. USB 4.0 will be compatible with the existing USB 4.0 first version, as well as previous USB 3.2 and USB 2.0. As for compatibility with Thunderbolt, the second version of USB 4.0 did not introduce compatibility with Thunderbolt 4, but still, like the first version, only compatible with Thunderbolt 3. Considering that in the first version of USB 4.0, compatibility with Thunderbolt 3 is only an option for the host and peripherals, and only the hub must be compatible, USB 4.0 second version may also use this design.

This backward compatibility is expected, but the second version of USB 4.0 seems to leave a surprise, which is that the existing USB 4.0 40Gbps cable can be upgraded to 80Gbps speed in the future, as confirmed by USB-IF spokesperson Joe Balich. USB-IF did not explain the technical principle of how to achieve this, but it is clear that wire is not the limiting factor, and the biggest upgrade is still on the protocol of the USB 4.0 controller.

But this compatibility is not for all USB 4.0 40Gbps Type-C cables, but only for passive USB cables. If you want to enjoy 80Gbps speed on an active USB cable of sufficient length, you still need to buy a new USB cable. So those users who want to experience greater bandwidth on VR devices and cameras for online shooting may have to spend money again.

Another chaotic naming

Since USB 3.0, the new USB standard has always maintained a relatively chaotic naming state. For example, USB 3.2 Gen 1 (formerly USB 3.0), USB 3.2 Gen 2 (formerly USB 3.1), and later USB 3.2 (USB 3.2 Gen 1x2 and USB 3.2 Gen 2x2). In addition, the marketing terms recommended by USB-IF that have never been widely used, such as full speed, high-speed, and overspeed, are often confused by terminal manufacturers when purchasing USB cables and devices.

However, it seems that the name USB 4.0 Second Edition is only for developers to see at present, and using it after landing on the product may be too catchy. For example, in USB 3.2Gen 1x2, Gen 1 refers to the clock speed per channel, where Gen 1 corresponds to 5Gbps, while x2 corresponds to the number of channels. Consumers do not need to know these, as long as their performance is known.

USB type-c cable trademark/USB-IF with power and performance labeling

According to the trademark applied by USB-IF, they are more willing to use speed as a differentiation rather than version number. So regardless of the name determined by the second version of USB 4.0, its product trademark should always read Certified USB 80Gbps. Not to mention that after the PD standard update, attention should be paid to the selection of wires to avoid the use of low charging power USB cables. Therefore, using trademarks to distinguish is the most intuitive, as shown in the above figure.

Which factories and chambers of commerce will follow up as soon as possible

As members of the USB promotion organization and advocates of Thunderbolt Interface, Apple and Intel will definitely be the first to follow up on this standard. In addition to cables, the first USB 4.0 second version products we see are likely to come from these two terminal products, as well as Intel's own USB/Thunderbolt chips. However, we all know that even for the current USB 4.0 support, these two companies are also the first to launch Thunderbolt 4 compatible with USB 4.0. As for other products under the USB 4.0 ecosystem, such as AMD platform notebooks, USB 4.0 Docking station, hubs, etc., it will take a while before they are launched in succession. Perhaps the terminal products of Thunderbolt 5 will be launched first.

As for the control chip and Retimer chip, in addition to Intel, Infineon and other manufacturers, most of them, especially several Taiwanese manufacturers, ASMedia, Purui Technology, Weifeng Electronics, etc., did not launch relevant USB 4.0 products until last year and this year, so it is bound to take some time to follow up the second version of USB 4.0.

Source: Electronic enthusiasts