Savvio 15K SAS Product Manual, Rev. B
9.5.2.3 Receiver signal characteristics
Table 18 defines the compliance point requirements of the signal at the receiver end of a TxRx connection as
measured into the test loads specified in figure 19 and figure 20.
a All tests in this table shall be performed with zero-length test load shown in figure 20.
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 20, 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.
Table 18: Receiver signal characteristics
Signal characteristic Units 1.5 Gbps 3.0 Gbps
Jitter (see figure 16)
b
N/A See table 19 See table 19
2 x Z2 mV(P-P) 1,200 1,600
2 x Z1 mV(P-P) 325 275
X1
a
UI 0.275 0.275
X2 UI 0.50 0.50
Skew
d
ps 80 75
Max voltage (non-op) mV(P-P) 2.000 2.000
Minimum OOB ALIGN burst amplitude
c
mV(P-P) 240 240
Maximum noise during OOB idle time
c
mV(P-P) 120 120
Max near-end crosstalk
e
mV(P-P) 100 100
a The value for X1 shall be half the value given for total jitter in table 19. The test or analysis shall include the effects of
a single pole high-pass frequency-weighting function that progressively attenuates jitter at 20 dB/decade below a
frequency of ((bit rate) / 1,667).
b The value for X1 applies at a total jitter probability of 10
-12
. At this level of probability direct visual comparison
between the mask and actual signals is not a valid method for determining compliance with the jitter output
requirements.
c With a measurement bandwidth of 1.5 times the baud rate (i.e. 4.5 GHz for 3.0 Gbps).
d 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 Rx+ and Rx- signals. Skew is
defined as the time difference between the means of the midpoint crossing times of the Rx+ signal and the Rx- signal.
e Near-end crosstalk is the unwanted signal amplitude at receiver terminals DR, CR, and XR coupled from signals and
noise sources other than the desired signal. Refer to SFF-8410.
Table 17: Transmitter signal characteristics
Signal characteristic
a
Units 1.5 Gbps 3.0 Gbps
