PORTS Forum

Ports and Interfaces => USB => Topic started by: KK_Omnisys on August 19, 2010, 02:20:40 am

Title: USB 3.0 FAQ confusion
Post by: KK_Omnisys on August 19, 2010, 02:20:40 am

I've been reading up on USB 3.0 at janaxelson.com but got confused when I got to the following part

Quote

How fast is USB 3.0?

USB 3.0 defines a new SuperSpeed bus with a bus speed of 5 Gbps, which is more than 10x faster than high-speed USB. After encoding and and other overhead, the bus can carry 400 MBps of data.

Does the above mean that the computer-to-hub bus speed is 5Gbps, but device-to-hub is maximum 400Mbit?

Then in a single device situation no benefit is claimed by the newer protocol or do I misinterpret?

Regards

KK

Title: Re: USB 3.0 FAQ confusion
Post by: Jan Axelson on August 19, 2010, 08:28:31 am

400 MBps = 400 Megabytes/sec, or 3,200 Megabits/sec of data for SuperSpeed. In contrast, the maximum data rate for a high-speed bus is about 53 Megabytes/sec.

Jan