Seagate ST973451SS 用户手册
Savvio 15K SAS Product Manual, Rev. B
65
9.5.2.3.4
Impedance specifications
Table 21 defines impedance requirements.
Table 21:
Impedance requirements (Sheet 1 of 2)
Requirement
Units
1.5 Gbps
3.0 Gbps
Time domain reflectometer rise time 20 % to 80 %
ps
100
50
Media (PCB or cable)
Differential impedance
ohm
100 ± 10
100 ± 10
Differential impedance imbalance
ohm
5
5
Common mode impedance
ohm
32.5 ± 7.5
32.5 ± 7.5
Mated connectors
Differential impedance
ohm
100 ± 15
100 ± 15
Differential impedance imbalance
ohm
5
5
Common mode impedance
ohm
32.5 ± 7.5
32.5 ± 7.5
Receiver termination
Differential impedance
ohm
100 ± 15
100 ± 15
Differential impedance imbalance
ohm
5
5
Receiver termination time constant
ps
150 max
100 max
Common mode impedance
ohm
20 min/40 max
20 min/40 max
Transmitter source termination
Differential impedance
ohm
60 min/115 max
60 min/115 max
Differential impedance imbalance
ohm
5
5
Common mode impedance
ohm
15 min/40 max
15 min/40 max