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USB 3.0

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"SuperSpeed" redirects here. For the superpower, see list of superhuman features and abilities in fiction.
USB 3.0
The Super-Speed USB Logo
Type USB
Production history
Designed 12, 2008
Manufacturer Apple Computer, Hewlett-Packard, NEC, Microsoft, Intel, and Agere Systems.
General specifications
Width 1
Data
Data signal Yes

USB 3.0 is the third major revision of the Universal Serial Bus (USB) standard for computer connectivity.

USB 3.0 has transmission speeds of up to 5 Gbit/s, which is 10 times faster than USB2.0 (480 Mbit/s). USB 3.0 significantly reduces the time required for data transmission, reduces power consumption, and is backwards compatible with USB 2.0. The USB 3.0 Promoter Group announced on 17 November 2008 that the specification of version 3.0 had been completed and had made the transition to the USB Implementers Forum (USB-IF), the managing body of USB specifications.[1] This move effectively opened the specification to hardware developers for implementation in future products.

The first USB 3.0 consumer products were announced and shipped by Buffalo Technology in November 2009, while the first certified USB 3.0 consumer products were announced 5 January 2010, at the Las Vegas Consumer Electronics Show (CES), including two motherboards by ASUS and Gigabyte Technology.[2][3]

Manufacturers of USB 3.0 host controllers include, but are not limited to, Renesas Electronics, Fresco Logic, Asmedia, Etron, VIA Technologies, Texas Instruments, NEC and Nvidia. As of November 2010, Renesas was the only company to have passed USB-IF certification, although Fresco Logic has also passed USB-IF certificiation. Motherboards for Intel's Sandy Bridge processors have been seen with Asmedia and Etron host controllers as well. On October 28, 2010 Hewlett-Packard released the HP Envy 17 3D featuring a Renesas USB 3.0 Host Controller several months before some of their competitors. AMD is working with Renesas to add its USB 3.0 implementation into its chipsets for its 2011 platforms. At CES2011 Toshiba unveiled a laptop called "Toshiba Qosmio X500" that included USB 3.0 and Bluetooth 3.0, and a new series of Sony VAIO laptops that will include USB 3.0. As of April 2011 the Inspiron and Dell XPS series are available with USB 3.0 ports.

Apple Inc. is the only major computer manufacturer without USB 3.0 equipped computers as of August 2011, opting to use another standard called Thunderbolt instead.[4]

Architecture And Features

In USB 3.0 dual-bus architecture is used to allow both USB 2.0 (HIGH Speed/LOW Speed/FULL Speed) and USB 3.0 (Super Speed) operations to take place simulataneously thus providing backward compatibility.Connections are such that they also permit forward compatability that is run USB 3 devices on USB 2.0 port.The structural topology is the same consists of a tiered star topology with a root hub at level 0 and hubs at lower levels to provide bus connectivity to devices.


Data Transfer And Synchronisation

The SuperSpeed transaction is initiated by the host making a request followed by a response from the device. The device either accepts the request or rejects it.If accepted then device sends data or accepts data from the host.If the endpoint is halted, the device shall respond with a STALL handshake. If there is lack of buffer space or data, it responds with a Not Ready (NRDY) signal to tell the host that it is not able to process the request. When the device is ready the , it will send an Endpoint Ready(ERDY) to the host which will then reschedule the transaction.

The use of unicasting and the limited multicasting of packets together with asynchronous notifications allows links that are not actively passing packets to be put into reduced power states.This allow better power management.

Data Bursting is used to enhance efficiency by eliminating the wait time for acknowledgements on a per data packet basis. Each endpoint on a SuperSpeed device indicates the number of packets that it can send/receive called the (maximum data burst size). before it has to wait for an explicit handshake.Maximum data burst size depends on an individual endpoint , a host determines an endpoint’s maximum data burst size from the SuperSpeed Endpoint Companion descriptor associated with that endpoint .The host may dynamically change the burst size in accordance with the transaction upto the maximum burst size. http://www.usb.org/.../1-2_SSUSB_DevCon_Arch_Overview_Dunstan.pdf


'Hot Plugging' Hubs are the key elements that account for the plug-and-play architecture of the USB. Hosts provide an implementation-specific number of downstream ports to which devices can be attached. Hubs provide additional downstream ports so they provide users with a simple connectivity expansion mechanism for the attachment of additional devices to the USB link. Plug and Play featue allow us to connect new devices to the system without restarting(hot-plugging).#REDIRECT [en.wikipedia.org/wiki/Plug_and_play]]




The "SuperSpeed" bus, which provides a fourth transfer mode at 5.0 Gbit/s. The raw throughput is 4 Gbit/s, and the specification considers it reasonable to achieve 3.2 Gbit/s (0.4 GB/s or 400 MB/s), or more, http://en.wikipedia.org/wiki/USB_3.0

Availability

Adding to existing equipment

USB 3.0 support can be added to existing laptop computers with only USB 2.0 and Expresscard support by using an Expresscard-to-USB 3.0 adapter to supply USB 3.0 signal support. Although the PCI Express port that the Express card connects cannot supply power of itself, the Express card and hence the USB 3 ports nevertheless derive power from the USB 2 port that it additionally connects to as part of the interface. If the express card has more than one USB 3 port then only 100mA is available from each port. Additional power for multiple ports may be derived in the following ways.

  • Some Expresscard-to-USB 3.0 adapters may connect by a cable to an additional USB 2.0 port on the computer, which supplies additional power.
  • The Expresscard may have a socket for an external power supply.
  • If the external device has an appropriate connector, it can be powered by an external power supply.

USB 3.0 support can be added as an expansion card to a desktop motherboard with PCI Express. (Similar cards are available for the older PCI standard, but few are available and they are more expensive.) If faster connections to storage devices are the reason to consider USB 3.0, an alternative is to use instead storage devices using eSATAp and add an inexpensive bracket adding an eSATAp port to the motherboard. Some external drives support both USB (2.0 or 3.0) and eSATAp with an exchangeable adapter, so the same drive can be used with a USB 3.0 laptop.[3] To ensure compatibility between motherboards and peripherals, all USB-certified devices must be approved by the USB Implementers Forum (USB-IF). At least one complete end-to-end test system for USB 3.0 designers is on the market.[5]

On 5 January 2010, USB-IF announced the first two certified USB 3.0 motherboards, one by Asus and one by Gigabyte.[3][6] Previous announcements included Gigabyte's October 2009 list of seven P55 chipset USB 3.0 motherboards,[7] and an ASUS motherboard that was cancelled before production.[8]

Left-hand side connectors on a Laptop. left to right, top to bottom: USB 3.0 host, VGA connector, DisplayPort connector, ExpressCard slot, USB2.0 host, radio kill switch. Note the extra connectors on the USB 3.0 host.

Commercial controllers were expected to enter into volume production in the first quarter of 2010.[9] On 14 September 2009, Freecom announced a USB 3.0 external hard drive.[10] On January 4, 2010, Seagate announced a small portable HDD with PC Card targeted for laptops (or desktop with PC Card slot addition) at the CES in Las Vegas Nevada.[11][12]

Drivers are under development for Windows 7, but support was not included with the initial release of the operating system.[13] However, drivers are available for Windows through manufacturer websites. The Linux kernel has supported USB 3.0 since version 2.6.31, which was released in September 2009.[14][15][16]

Intel decided not to support USB 3.0 until 2011,[17] which will slow down mainstream adoption. These delays may be due to problems in the CMOS manufacturing process,[18] a focus to advance the Nehalem platform,[19] a wait to mature all the 3.0 connections standards (USB 3.0, PCIe 3.0, SATA 3.0) before developing a new chipset,[20][21] or a tactic by Intel to boost its new Thunderbolt interface.[22] Current AMD road maps indicate that the new southbridges released in the beginning of 2010 will not support USB 3.0.[18]

Speed issues

There have been many reports of USB 3.0 equipment only transferring data at USB 2.0 speed, usually with a message "This USB Mass Storage Device can transfer information faster if you connect it to a Super-Speed USB 3.0 port". This has been due to several causes, including drivers, certain cables specified as USB 3.0 (problems disappeared when a different cable was used), order of starting equipment, equipment needing to be disconnected and reconnected, and overclocked computers.[23]

Connectors

Standard-A

A USB 3.0 Standard-A receptacle accepts either a USB 3.0 Standard-A plug or a USB 2.0 Standard-A plug.Conversely its possible to plug USB 3.0 Standard-A plug into a USB 2.0 Standard-A receptacle.The Standard-A is used for connecting to the computer port.

The connector has the same physical configuration as its predecessor but with more pins for USB 3.0 .The VBUS, D-, D+, and GND pins are required for USB 2.0 support,while for USB 3.0 Standard-A connector five more pins are included–two differential pairs and one ground (GND_DRAIN). The are two additional differential pairs are for SuperSpeed data transfer, that support dual simplex SuperSpeed signaling; while the GND_DRAIN pin is for drain wire termination,and to control EMI and maintain signal integrity. Since USB 2.0 and USB 3.0 ports may coexists on the same machine and look similar USB 3.0 Connector is Blue (Pantone 300C) in colour.


USB 3.0 pinouts[24]
Pin Color Signal name
('A' connector)		 Signal name
('B' connector)
1 Red VBUS
2 White D−
3 Green D+
4 Black GND
5 Blue StdA_SSRX− StdA_SSTX−
6 Yellow StdA_SSRX+ StdA_SSTX+
7 Shield GND_DRAIN
8 Purple StdA_SSTX− StdA_SSRX−
9 Orange StdA_SSTX+ StdA_SSRX+
Shell Shell Shield
USB 3.0 Standard-A connector
USB 3.0 Standard-A connector

The USB 3.0 Standard-B connector is defined for large,stationary peripheral devices,like external hard drives and printers. It is defined so that the USB 3.0 Standard-B receptacle accepts either a USB 3.0 Standard-B plug or a USB 2.0 Standard-B plug. However, inserting a USB 3.0 Standard-B plug into a USB 2.0 Standard-B receptacle is disallowed

See also

References

  1. ^ "USB‐IF" (PDF). Retrieved 2010-06-22.
  2. ^ "First Certified USB 3.0 Products Announced". PC World. 2010-01-07. Retrieved 2010-06-22.
  3. ^ a b c SuperSpeed USB Consumer Cert Final 2 (PDF), USB‐IF.
  4. ^ "Thunderbolt: Next-Generation high-speed I/O technology". Apple. February 24, 2011. Retrieved February 25, 2011.
  5. ^ "USB 3". Lecroy. Retrieved 2010-06-22.
  6. ^ Both Gigabyte and Asus claimed the "first" USB 3.0 motherboard, Gigabyte, USA, 2010 January 4 {{citation}}: Check date values in: |date= (help)[dead link] and Asus, USA, 2010 January 6 {{citation}}: Check date values in: |date= (help), while the official announcement (PDF), USB-IF, 2010 January 5 {{citation}}: Check date values in: |date= (help).
  7. ^ Gibabyte, TW[dead link].
  8. ^ "Asus cancels its first usb 3.0 motherboard". The Inquirer. Retrieved 2010-06-22.
  9. ^ "Digitimes". 2009-04-15. Retrieved 2010-06-22.
  10. ^ "Freecom.com". Retrieved 2010-06-22.[dead link]
  11. ^ Ngo, Dong (2010-01-05). "Seagate ships USB 3.0-based external hard-drive kit for laptops | CES". CNET. Retrieved 2010-06-22.
  12. ^ "BlackArmor PS 110 with USB 3.0 | Portable Hard Drive for Business with Backup Software". Seagate. Retrieved 2010-06-22. [dead link]
  13. ^ "USB in MS Windows 7 more reliable, but no 3.0 speed boost". APC Mag. Retrieved 2010-06-22.
  14. ^ "Kernel newbies". 2009-09-09. Retrieved 2010-06-22.
  15. ^ "Erste USB 3.0 Treiber". DE: Heise. 2009-12-03. Retrieved 2010-06-22. {{cite web}}: Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)
  16. ^ "First driver for USB 3.0". Linux magazine. 2009-06-09. Retrieved 2010-06-22.
  17. ^ "EE Times". Retrieved 2010-06-22.
  18. ^ a b Spekulationen über Verzögerungen bei USB 3.0 (in German), DE: Heise
  19. ^ Paul Mah (2009-10-23). "Fiercecio.com". Fiercecio.com. Retrieved 2010-06-22.
  20. ^ "FAQ — PCI Express 3.0". PCI SIG. 2009-07-01. Retrieved 2010-06-22.
  21. ^ "PCIe 3.0 Specification Coming Soon". Enterprise storage forum. 2010-05-05. Retrieved 2010-06-22.
  22. ^ "Intel delays USB 3.0 support until 2011". Techspot. 2009-10-22. Retrieved 2010-06-22.
  23. ^ USB 3.0 with "The Device can perform Faster", Tom's hardware.
  24. ^ "USB 3.0 Interface Bus, Cable Diagram". 100806 interfacebus.com


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