USB4 Version 2.0 supports up to 120Gbit/s asymmetric for displays

The USB Implementers Forum has published the full USB4 Version 2.0 specifications. The Forum previously said that the second version of USB4 supports symmetrical bandwidth of 80Gbit/s and now says that asymmetrical 120Gbit/s is also possible.

That 120Gbit/s is intended for ‘certain applications, such as very-high performance USB4 displays’, writes USB-IF. Then 120Gbit/s goes to the screen and data with a bandwidth of up to 40Gbit/s can be sent in the opposite direction.

USB4 Version 2.0 continues to work with a new physical layer architecture based on pam 3 modulation. The Forum previously said that this would enable symmetric speeds of 80Gbit/s to be achieved, both on existing passive USB4-Type-C cables and with new, active 80Gbit/s Type-C cables. With an active cable, there is electronics in the cable that amplifies the signal, making longer cables possible.

The new specification also includes updates for USB 20Gbit/s SuperSpeed ​​cables, making them faster than 20Gbit/s. How much faster is not yet clear. USB4 Version 2 is “in-line” with DisplayPort 2.1 and PCIe 4 according to USB-IF.

By sharing the specifications, developers and manufacturers can get started creating USB4 Version 2.0 products. It is not the intention that certified manufacturers will use USB4 Version 2 in their communication to consumers, but will talk about USB 80Gbps. It is not clear whether manufacturers will do this in practice. The Forum speaks to CNET it is expected that it will take another 12 to 18 months for the first USB4 Version 2 products to appear.