USB 3.1 provides faster data transfer speeds of up to 10Gbps, which is twice as fast as USB 3.0. It was created to meet the increasing needs for transferring large files like HD videos. USB 3.1 has two main goals - improved performance and backward compatibility with older USB standards. It uses a new reversible Type-C connector that allows for easier plugging and faster charging compared to previous connectors. Compliance testing also focuses on meeting the new electrical and transfer speed requirements for USB 3.1.

1. USB 3.1
Universal Serial Bus.
Rainny
rainny.tu@gmail.com
2016/08/31 update.

2. Agenda
• Introduction
– What is USB?
– History of USB.
• USB 3.1
– Why is USB 3.1?
– Design Goals.
– Compare
• Type-C
• Applications of Type-C
• Compliance
• Q&A
2

3. What is USB?
• Universal Serial Bus. (USB)
• User-friendly.
• Plug-and-play way for device and host.
• Do not need install device’s driver in computer.
• A standard bus to connector device to host
computer.
3

4. History of USB
Jan, 1996
USB1.0
1.5Mbps
Low Speed
Sep, 1998
USB1.1
12Mbps
Full Speed
Apr, 2000
USB2.0
480Mbps
Hi Speed
Nov, 2008
USB3.0
5Gbps
Super Speed
Jul, 2013
USB3.1
10Gbps
Super Speed +
Logo: USB-IF
4

5. Why is USB 3.1?
• USB / HDMI / Thunderbolt Data Rate
USB3.0 has lower rate of other usual device.
5

6. Why is USB 3.1?
• We have large data everyday.
Such as HDD, DVD, BR-DVD, HD TV, Ultra HD TV.
• People demand higher performance between host
and peripheral.
6
• Improve EMI performance & effect.
USB 3.0 will affect some device. (like wireless LAN
Card)

7. • Smart host and simple device.
• Improve power management.
• Ease of use .
• Backward compatibility 2.0 at Type-A
connector.
• Take advantage of USB 3.1 without change OS.
7
USB 3.1 Design Goals

8. Compare - Cable
Characteristic USB3.1 USB3.0 USB 2.0
Data Interface
Type-A
Connector Pinout
Cable Length 1 Meter 3 Meter 5 Meter
PCB Trace Length 8 Inch (20.32cm) 12 Inch (30.48cm)
• About Cable.
8

9. Compare – Data Rate
Characteristic USB3.1 USB3.0 USB 2.0
Speed SuperSpeed Plus SuperSpeed HiSpeed
Data Rate 10 Gbps (Gen 2) 5.0 Gbps (Gen 1) 480Mbps
Encoded
Mode
128b/132b 8b/10b 8b/10b
Encoded Loss -3.03% (96.97%) -20% (80%) -20% (80%)
Actual Rate
10Gb/s * (128/132)
= 9.697Gb/s
= 1.21GB/s
5Gb/s * (8/10)
= 4Gb/s
= 500MB/s
480Mb/s * (8/10)
= 384Mb/s
= 48MB/s
• About Data Rate.
* USB3.1 (Gen 2) real transfer speed is up to x2.4 of USB3.0.
9

10. Compare - Connector
• Review USB 2.0 & USB 3.0 connector.
10

11. Type-C
• About USB 3.1 connector
• Type-A : the same as USB 3.0 Type A.
• Type-C : Release by USB.org in 2015 April.
USB.org want to let Type C become the common
connector of mobile devices.
• Existing USB connector is difficult to use.
New connector is no directionality.
11
• Backward compatibility.

12. 12
• Plug-unplug over 10,000 times.
• Support large power charging. (According to PD spec.)
Supply peripheral or mobile device with up to 100W.
Need to add ICs to control.
• Increased data channels. (Ideal)
Two pairs of Tx/Rx signal paths.
Provide total bandwidth of 20Gbps.
• Thunderbolt 3 connector.
(release: June, 2015)
Data rate: 40Gb/s ~= 5GB/s
Type-C

13. • Let’s see how does it look like.
13
Type-C
Photo by rainny.

14. Type-C
• USB Type-C Pin defined.
14
Fig 2-1/2-2: USB3.1 spec.
- Receptacle Configuration.
- Plug Configuration. (for cable and device)
- Plug can insert into receptacle. Also can rotate 180˚.

15. • Let’s check the receptacle side of system or device.
15
Type-C
• D+/D-: signal path for USB2 only.
• Vbus/GND: Power for USB.
Also implement large power charging. Can deliver up to 100W.
• Tx1/2, Rx1/2: 2 channels of SuperSpeed+ data links.
• CC1/CC2: Configuration channel. Detect connections and
interface.
• SBU1/ 2: Sideband use pins. Non-USB signals.
Usually used in Audio mode.

16. Applications of Type-C
• ex. USB Type-C to DisplayPort
16
• DisplayPort can use all of the high speed paths to deliver.
• Type-C side can be reversible.
• Also can support HDMI, DVI, VGA cable.

17. Compliance
• Updating compliance plans & specs.
• Host/ Devices will be test for:
– Support USB 2.0 speeds.
– Meet Superspeed(Gen1) requirements.
– Meet Superspeed+(Gen2) requirements.
• USB 3.1 Compliance Requirement
– New electrical test for physical layer.
– New cable and connector test.
17

18. • Compare with the basic spec.
18
Compliance
Table 6-17/ 6-19: USB3.1 spec.

19. • Eye Diagram.
19
Compliance
Eye Diagram: USB3.1 spec.

20. Conclusion
• High performance.
USB 3.1 provide data rate up to 10Gbps, 2x of USB3.0.
• Conveniently.
Standard connector, has no directionality.
• Less lose of encoder. Efficiency is improved up.
• No driver software changes required.
• EMI performance upgrade.
Improved shielding and grounding of connector.
20

21. Thanks.
21

22. Q & A
22