Seagate ST600MP0074, Руководство по эксплуатации продукта

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60 Savvio 15K SAS Product Manual, Rev. B
Table 16 defines the general interface characteristics.
9.5.2.1 Eye masks
9.5.2.1.1 Eye masks overview
The eye masks are graphical representations of the voltage and time limits on the signal at the compliance
point. The time values between X1 and (1 - X1) cover all but 10
-12
of the jitter population. The random content
of the total jitter population has a range of
±
7 standard deviations.
9.5.2.1.2 Receive eye mask
Figure 16 describes the receive eye mask. This eye mask applies to jitter after the application 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).
Figure 16. Receive eye mask
Verifying compliance with the limits represented by the receive eye mask should be done with reverse channel
traffic present in order that the effects of crosstalk are taken into account.
Table 16: General interface characteristics
Characteristic Units 1.5 Gbps 3.0 Gbps
Bit rate (nominal) Mbaud 1,500 3,000
Unit interval (UI)(nominal) ps 666.6 333.3
Impedance (nominal, differential ) ohm 100 100
Transmitter transients, maximum V
±
1.2
±
1.2
Receiver transients, maximum V
±
1.2
±
1.2
Absolute
amplitude
(in V)
Z1
Z2
0 V
-Z1
-Z2
X1 X2
1-X2
1-X1
Normalized time (in UI)
0 1