USB-IF officially publishes the technical specifications of `` USB4 '' with a maximum transfer speed of 40 Gbps and 8 times faster than USB 3.0

by GEEK KAZU

The USB Implementers Forum (USB-IF), a non-profit organization that promotes the spread of USB, released version 1.0 of the USB4 technical specification, a new USB standard, to manufacturers on September 3, 2019. Although the specification itself has already been finalized, the USB-IF officially publishes the technical specifications, and the development of products that adopt USB4 will be promoted.

USB4 ™ Specification | USB-IF
https://www.usb.org/document-library/usb4tm-specification

USB 4: Everything We Know So Far
https://www.tomshardware.com/news/usb-4-faq,38766.html

The provisional specification of USB4 was announced in March 2019 by the industry group “USB Promoter Group” that develops USB specifications. According to it, the shape of the terminal is USB Type-C, backward compatibility with USB 2.0 and USB 3.2 is maintained, and the maximum transfer speed when using a certified cable was up to 40 Gbps.

Provisional specification of new standard `` USB 4 '' assuming transfer speed of up to 40 Gbps will be announced-gigazine

The official specification of USB4 officially released by USB-IF is almost the same as the provisional specification. The connection terminal of USB4 developed based on Thunderbolt 3 is USB Type-C, and communication of up to 40Gbps is possible by using a certified cable. This maximum communication speed is twice that of USB 3.2 Gen 2x2 and 8 times that of USB 3.2 Gen 1x1 (USB 3.0). However, this maximum communication speed is a theoretical value, and not all devices support it.

Brad Sanders, CEO of USB Promoter Group, said tom's HARDWARE, a technical media, “There are three stages of USB4 communication speed: 10 Gbps, 20 Gbps, and 40 Gbps. Most PCs equipped with USB4 are Thunderbolt 3 It will work. '

In addition, USB4 can be connected to the display, send and receive data, and send and receive power simultaneously. For example, if you want to copy a large amount of files from an external SSD with a USB4 and certified cable and output it to a 4K monitor, if you need 12.5 Gbps for the video signal bandwidth, you can use the remaining 27.5 Gbps for sending and receiving files That's why.

In addition, as indicated in the preliminary specification announced in March, backward compatibility with USB 3.2, USB 2.0, and Thunderbolt 3 is also specified in the USB4 specification. Thunderbolt 3 is a data transmission technology jointly developed by Intel and Apple, and a license was required to adopt Thunderbolt 3 in the product. However, in May 2017 Intel decided to free Thunderbolt 3 royalty. This makes it easy to make Thunderbolt 3 compatible even for products from manufacturers other than Intel, and has become the basis for the USB4 specification.

Intel introduces Type-C compatible `` Thunderbolt 3 '' in the CPU & announces royalty-free, summary of how it will be convenient with the spread of Thunderbolt-GIGAZINE

The official name of the standard is “USB4”, and unlike “USB 2.0” or “USB 3.2”, there is no space between “USB” and “4”. Saunders explains, “To focus on the brand name from the version number”.

For example, even in the standard called USB3.2, there are 4 versions of 'USB 3.2 Gen 1x1', 'USB 3.2 Gen 1x2', 'USB 3.2 Gen 2x1', and 'USB 3.2 Gen 2x2'. However, among them, USB 3.2 Gen 1x1 is the previous USB 3.0, USB 3.2 Gen 2x1 is the previous USB 3.1, and criticism that the overly confused USB standard name is causing excessive confusion for consumers and the market There was also.

USB's next standard `` USB3.2 '' boasting a transfer rate of 20 Gbps is expected to be installed on PC in 2019-GIGAZINE

“One thing I want to say right now is that I'm not going to name USB 4.0, USB 4.1, USB 4.2…. USB4 is a unique architecture with its own speed, “We will not release in decimal notation, and if we can speed up from USB4, we will only create a faster version of the certification and brand,” says Sanders. The USB 3.2 connection is named “SuperSpeed USB”, but the name of the USB4 connection has not yet been announced.