Figure 21 shows the zero-length test load.

10 nF

50 ohm

Tx+

 

Probe

 

points

 

10 nF

50 ohm

Tx-

SAS internal connector

Figure 21. Zero-length test load

Figure 22 shows an ISI loss example at 3.0 Gbps.

S21 (dB)

 

 

 

 

Compliance interconnect magnitude response and

 

 

ISI loss example for 3.0 Gbps

0

 

 

ISI loss

 

 

> 3.9 dB

 

 

-10.9 dB

 

Sample compliance interconnect

 

 

0.3

1.5

Frequency (GHz)

3.0

Figure 22. ISI loss example at 3.0 Gbps

Figure 23 shows an ISI loss example at 1.5 Gbps.

S21 (dB)

 

 

 

 

 

 

 

 

Compliance interconnect magnitude response and ISI

 

 

 

0

 

 

 

loss example for 1.5 Gbps

 

ISI loss

 

 

 

 

 

 

> 2.0 dB

 

 

 

 

 

-5.4 dB

 

 

 

 

Sample compliance interconnect

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Frequency (GHz)

0.15

0.75

1.5

 

 

 

Figure 23. ISI loss example at 1.5 Gbps

72

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

Page 78
Image 78
Seagate ST3146356SS, ST3300656SS, ST3450856SS manual Shows the zero-length test load