USB4 released official specifications “8 times faster than 3.0”

On September 3, the USB Implementers Forum (USB-IF), a non-profit organization promoting USB dissemination, released version 1.0 of the USB4 technical specification, a new standard for USB. The specification itself has already been developed, but development of USB4 adopting products will proceed as USB-IF officially discloses the technical specifications.

USB4’s port type maintains backward compatibility with USB Type C, USB 2.0, and USB 3.2, and the maximum transmission speed is 40Gbps when a certified cable is used.

The official specifications for USB4, officially released by USB-IF, are almost the same as the tentative specifications. The USB4 connection terminal developed based on Thunderbolt 3 can communicate up to 40Gbps using a USB Type C certified cable. This speed is twice that of USB 3.2 Gen 2×2 and 8 times that of USB 3.2 Gen 1×1. However, this maximum communication speed is a theoretical value and not all devices support it.

Brad Saunders, CEO of USB-IF, said that USB4 has three levels of communication speeds of 10, 20, and 40Gbps. Most PCs with USB4 will run Thunderbolt 3.

In addition, USB4 can connect the display and transmit and receive data at the same time. For example, if a large number of files are copied from an external SSD via USB4 and an authentication cable and output to a 4K monitor at the same time, if a video signal bandwidth of 12.5Gbps is required, the remaining 27.5Gbps can be used for file transmission and reception.

As stated in the tentative specification released in March, compatibility with USB 3.2 and 2.0 and Thunderbolt 3 is also specified in the specification. Thunderbolt 3 is a data transmission technology jointly developed by Intel and Apple. The adoption of Thunderbolt 3 in the product required a license. But in May 2017, Intel decided to make the Thunderbolt 3 Royal Fee Free. Accordingly, it is easy to have Thunderbolt 3 compatibility for products from manufacturers other than Intel, and it is based on the USB4 specification.

The official name of this standard is USB4. Unlike USB 2.0 or 3.2, there is no space between USB and 4. In response, Sanders’ CEO explains that the version name is intended to focus on the brand. For example, there are four versions of USB 3.2 Gen 1×1, Gen 1×2, Gen 2×1, and Gen 2×2 only within the specification of USB 3.2. Due to this, there have been criticisms that the name of the USB standard is scattered, causing excessive confusion in consumers and markets.

It is not going to be named something like USB 4.0 or 4.1 anymore. USB4 is said to be not released with decimal marks for each speed. If USB4 promotes speed improvement, it will show faster version certification and brand. Other than that, USB 3.2 was named SuperSpeed ​​USB, but USB4 has not yet announced such a name. Related information can be found here .