Seagate ST300MM0026 Savvio 10K.1 SAS Product Manual - Page 68

Eye masks, 5.2.1.1, Eye masks overview, 5.2.1.2, Receive eye mask, Table 26, General

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Table 26 defines the general interface characteristics. Table 26: General interface characteristics Characteristic Bit rate (nominal) Unit interval (UI)(nominal) Impedance (nominal, differential ) Transmitter transients, maximum Receiver transients, maximum Units Mbaud ps ohm V V 1.5 Gbps 1,500 666.6 100 ± 1.2 ± 1.2 3.0 Gbps 3,000 333.3 100 ± 1.2 ± 1.2 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 19 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). Absolute amplitude (in V) Z2 Z1 0 V -Z1 -Z2 0 X1 X2 1-X1 1 1-X2 Normalized time (in UI) Figure 19. 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. 62 Savvio SAS Product Manual, Rev. D

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62
Savvio SAS Product Manual, Rev. D
Table 26 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 19 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 19.
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 26:
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