Architecture and features įront view of a Standard-A USB 3.0 connector, showing its front row of four pins for the USB 1.x/2.0 backward compatibility, and a second row of five pins for the new USB 3.0 connectivity.
This gives USB 3.0 a potential total bidirectional bandwidth twenty times greater than USB 2.0.
USB 3.0 has transmission speeds of up to 5 Gbit/s, about ten times faster than USB 2.0 (0.48 Gbit/s) even without considering that USB 3.0 is full duplex whereas USB 2.0 is half duplex. Support for rotating media – the bulk protocol is updated with a new feature called Stream Protocol that allows a large number of logical streams within an Endpoint.Improved bus use – a new feature is added (using packets NRDY and ERDY) to let a device asynchronously notify the host of its readiness, with no need for polling.Power management – U0 to U3 link power management states are defined.
It is recommended that manufacturers distinguish USB 3.0 connectors from their USB 2.0 counterparts by using blue color for the Standard-A receptacles and plugs, and by the initials SS.
Among other improvements, USB 3.0 adds the new transfer rate referred to as SuperSpeed USB (SS) that can transfer data at up to 5 Gbit/s (500 MB/s after encoding overhead), which is about 10 times faster than Hi-Speed (maximum for USB 2.0 standard).
USB 3.0, released in November 2008, is the third major version of the Universal Serial Bus (USB) standard for interfacing computers and electronic devices. USB 3.0 Promoter Group ( Hewlett-Packard, Intel, Microsoft, NEC, ST-Ericsson, and Texas Instruments) ġ2 mm (A plug), 8 mm (B plug), 12.2 mm (Micro-A & Micro-B plugs)Ĥ.5 mm (A plug), 10.44 mm (B plug), 1.8 mm (Micro-A & Micro-B plugs)