USB 3.0 spec finalized
By Wolfgang Gruener
Monday, November 17, 2008 11:33
San Jose (CA) - The USB 3.0 Promoter Group today announced the completion of the USB 3.0 specification. The new interface technology provides ten times the bandwidth of its predecessor and is expected to be integrated in future designs of consumer electronics and PC peripheral devices. But even if hardware designers are adopting the technology immediately, don’t expect USB 3.0 to appear anytime soon on store shelves.
Following Apple’s decision to abandon its Firewire technology at least in some of its systems and acknowledging that USB is ubiquitous in today’s computer and electronics landscape paves the way for a simpler interface technology in the future. And it is exact at this time when USB begins to surpass the bandwidth of Firewire (IEEE1394).
The USB 3.0 Promoter Group today announced that version 1.0 of the USB 3.0 specification has been completed and is transitioned to the USB Implementers Forum (USB-IF), the managing body of USB specifications. This move effectively opens the spec to hardware developers for implementation in future products. At the most recent IDF, we got a first taste how these devices will work and perform. The technology will provide a maximum bandwidth of 5.0 Gb/s, which is more than six times what is offered buy USB 2.0 (480 Mb/s), which was released more than eight years ago in April of 2000. For those who have been around for some time, USB 1.0 was introduced in 1996 and described an interface that transferred data at 1.5 Mb/s. USB 1.1 followed in 1998 with a 12 Mb/s spec.
USB 3.0 will remain backwards compatible with USB 2.0 as far as the Type A connector is concerned. The technology of USB 3.0 is vastly different, though. While USB 2.0 is based on uni-directional data flow with negotiated directional bus transitions, USB 3.0 supports simultaneous bi-directional data flows through the use of dual-simplex four-wire differential signal wiring as compared to half-duplex two wire differential wiring in USB 2.0. Other interesting innovations in USB 3.0 include new power management features that support idle, sleep and suspend states.
Last month, Tektronix was first to announce test tools for USB 3.0, which enables developers to verify silicon compliance with the specification and test hardware designs.
USB 3.0, which will be called USB SuperSpeed in commercial devices, is expected to be available in commercial controllers in the second half of 2009. Consumer products are expected to become available in 2010.
Major industry players such as Apple seem to have lost interest in Firewire. However the IEEE recently approved the IEEE 1394-2008 specification, which increases the interface bandwidth of IEEE1394, also known as Firewire and i.Link, to 3.2 Gb/s.