On July 2013, a new version of USB specification was released and officially published in August 2014: USB 3.1 or Super Speed +.
What’s different in this new specification? Data rate, power delivery features and new connector type but still backward compatible with USB 3.0 & 2.0 standards. Therefore, it is a huge step forward and with this improvement, a universal communication protocol may be established.
When USB 2.0 was able to transfer data at 480 Mbps and USB 3.0 at 5 Gbps, USB 3.1 can achieve 10 Gbps data rate. For comparison purpose, a 25 GB HD movie could now be transferred in just more than half a minute against 70 seconds with USB 3.0 protocol.
Standard USB 3.1 connectors will be able to supply more power than USB 3.0 (9 W for A, B and Micro B and 15 W for Type C vs 4.5 W before).
Type A connector remains retro compatible but design will slightly change with shielding reinforcement. On Power-Delivery compatible connector, two detection pins are added for insertion and power:
Type B & Micro Type designs have some extra-shielding but are really close to USB 3.0 (EMI-RFI performance increase). Besides high transfer rate aspects, one of the main reasons why USB 3.1 is highly awaited is the new reversible connector: Type C.
It is a widespread problem that it often takes several attempts to plug in a USB until it finally works. For this reason, a native reversible solution with both receptacles and plugs has now been developed.
More than this feature, Type C connector will be able to handle 15 W (3 A under 5 V) and with a connector size close to Mini USB. For supporting reversibility, 24 pins are needed and pin-out will follow:
Full-feature plug has “only” 22 pins because B6 & B7 contacts are not implemented for avoiding cross-talk issues and extra-stubs.
To guarantee compatibility with USB 2.0 and 3.0 standards, cables and adapters will be developed and plating of USB connectors and plugs will be realized in Palladium-Nickel for improving cost-efficiency, still ensuring mating cycles requirements of USB-IF specification.
