9.5.2.3.2Receiver jitter tolerance

Table 32 defines the amount of jitter the receiver shall tolerate .

Table 32:

Receiver jitter tolerance

 

 

 

 

 

 

 

 

 

 

 

1.5 Gbpsa

 

 

 

3.0 Gbpsa

 

 

Sinusoidal

 

Deterministic

Total

Sinusoidal

Deterministic

Total

jitterb,c

 

jittere,f,h

jitterh

jitterb,d

jittere,g,h

jitterh

0.10

 

0.35

0.65

0.10

0.35

0.65

 

 

 

 

 

 

 

aUnits are in UI.

bThe jitter values given are normative for a combination of deterministic jitter, random jitter, and sinusoidal jitter that receivers shall be able to tolerate without exceeding a BER of 10-12. Receivers shall tolerate sinusoidal jitter of progressively greater amplitude at lower frequencies, according to the mask in figure 20 with the same deterministic jitter and random jitter levels as were used in the high frequency sweep.

cSinusoidal swept frequency: 900 kHz to > 5 MHz.

dSinusoidal swept frequency: 1.800 kHz to > 5 MHz.

eNo value is given for random jitter. For compliance with this standard, the actual random jitter amplitude shall be the value that brings total jitter to the stated value at a probability of 10-12. The additional 0.1 UI of sinusoidal jitter is added to ensure the receiver has sufficient operating margin in the presence of external interference.

fDeterministic jitter: 900 kHz to 750 MHz.

gDeterministic jitter: 1.800 kHz to 1.500 MHz.

hThe deterministic and total values in this table apply to jitter after 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).

9.5.2.3.3Compliant jitter test pattern (CJTPAT)

The CJTPAT within a compliant protocol frame is used for all jitter testing unless otherwise specified. See the SAS Interface Manual for definition of the required pattern on the physical link and information regarding spe- cial considerations for scrambling and running disparity.

9.5.2.3.4Impedance specifications

Table 33 defines impedance requirements.

Table 33: 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

Cheetah 15K.6 SAS Product Manual, Rev. B

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Seagate ST3146356SSIM manual Receiver jitter tolerance, Compliant jitter test pattern Cjtpat, Impedance specifications