Seagate ST3450802SS ユーザーズマニュアル

56

Cheetah NS 10K.2 SAS Product Manual, Rev. C

Table 25 specifies the signal requirements at the transmitter end of a TxRx connection as measured into the 
zero-length test load. All specifications are based on differential measurements.

The OOB sequence is performed at signal voltage levels corresponding to the lowest supported transfer rate. 
Table 25 specifies the signal characteristics.

ps

20

15

Tx Off Voltage

mV(P-P)

< 50

< 50

Maximum rise/fall time

ps

 273

137

Minimum rise/fall time

ps

67

67

Maximum transmitter output imbalance

%

10

10

OOB offset delta

mV

± 25

± 25

OOB common mode delta

mV

± 50

± 50

a All tests in this table shall be performed with zero-length test load shown in figure 18.
b The skew measurement shall be made at the midpoint of the transition with a repeating 0101b pattern on the physical 

link. The same stable trigger, coherent to the data stream, shall be used for both the Tx+ and Tx- signals. Skew is 
defined as the time difference between the means of the midpoint crossing times of the Tx+ signal and the Tx- signal.

c The transmitter off voltage is the maximum A.C. voltage measured at compliance points when the transmitter is 

unpowered or transmitting D.C. idle (e.g., during idle time of an OOB signal).

d Rise/fall times are measured from 20 % to 80 % of the transition with a repeating 0101b pattern on the physical link.
e The maximum difference between the V+ and V- A.C. RMS transmitter amplitudes measured on a CJTPAT test 

pattern (see 9.5.2.3.3) into the test load shown in figure 18, as a percentage of the average of the V+ and V- A.C. 
RMS amplitudes.

f The maximum difference in the average differential voltage (D.C. offset) component between the burst times and the 

idle times of an OOB signal.

g The maximum difference in the average of the common mode voltage between the burst times and the idle times of 

an OOB signal.