Seagate ST936751SS, ST973451SS manual Impedance specifications, Impedance requirements Sheet 1 of

9.5.2.3.4Impedance 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 %a,b	ps	100	50
Media (PCB or cable)
Differential impedanceb,c,d	ohm	100 ± 10	100 ± 10
Differential impedance imbalanceb,c,d,g	ohm	5	5
Common mode impedanceb,c,d	ohm	32.5 ± 7.5	32.5 ± 7.5
Mated connectors
Differential impedanceb,c,d	ohm	100 ± 15	100 ± 15
Differential impedance imbalanceb,c,d,g	ohm	5	5
Common mode impedanceb,c,d	ohm	32.5 ± 7.5	32.5 ± 7.5
Receiver termination
Differential impedanceb,e,f	ohm	100 ± 15	100 ± 15
Differential impedance imbalanceb,e,f,g	ohm	5	5
Receiver termination time constantb,e,f	ps	150 max	100 max
Common mode impedanceb,e	ohm	20 min/40 max	20 min/40 max
Transmitter source termination
Differential impedanceb	ohm	60 min/115 max	60 min/115 max
Differential impedance imbalanceb,g	ohm	5	5
Common mode impedanceb	ohm	15 min/40 max	15 min/40 max

Savvio 15K SAS Product Manual, Rev. B 65