７５
2.8 USB3.0
USB 3.0 is the third major revision of the Universal Serial Bus (USB) standard for computer connectivity.
It adds a new transfer speed called SuperSpeed (SS) to the already existing LowSpeed (LS), FullSpeed
(FS) and HighSpeed (HS).
USB 3.0 leverages the existing USB 2.0 infrastructure by adding two additional data pair lines to allow a
transmission speed up to 5 Gbit/s, which is 10 times faster than USB 2.0 with 480 Mbit/s.
The additional data lines are unidirectional instead of the bidirectional USB 2.0 data lines. USB 3.0 is
fully backward compatible to USB 2.0. USB 3.0 connectors are different from USB 2.0 connectors. The
USB 3.0 connector is a super set of a USB 2.0 connector, with 4 additional pins that are invisible to USB
2.0 connectors. A USB 2.0 Type A plug may be used in a USB 3.0 Type A receptacle, but the USB 3.0
SuperSpeed functions will not be available.
2.8.1 USB3.0 Signal Definitions
Table 24:
USB3.0 Signal Definitions
Signal
Pin#
Description
I/O
Note
US
USB_SSTX0-
D4
D3
USB Port 0, SuperSpeed TX +
USB Port 0, SuperSpeed TX –
Module has integrated AC Coupling Capacitors
Carrier Board:
Device - Connect to St/-
Conn. - Connect 0Ω and 90Ω @100MHz USB3.0
Common Mode Choke(NL) combined in series and
USB3.0 ESD suppressors to GND to Pin 9
St / Pin 8 StdA_SSTX-, the value of CMC
depends on EMI and signal integrity performance.
N/C if not used
O PCIE
US
USB_SSTX1-
D7
D6
USB Port 1, SuperSpeed TX +
USB Port 1, SuperSpeed TX –
Module has integrated AC Coupling Capacitors
Carrier Board:
Device - Connect to St/-
Conn. - Connect 0Ω and 90Ω @100MHz USB3.0
Common Mode Choke(NL) combined in series and
USB3.0 ESD suppressors to GND to Pin 9
St / Pin 8 StdA_SSTX-, the value of CMC
depends on EMI and signal integrity performance.
N/C if not used
O PCIE
