Seagate ST31000640SS, ST3750630SS, ST3500620SS manual Shows the zero-length test load

Figure 20 shows the zero-length test load.

Tx+	10 nF	50 ohm
	Probe
	points
Tx-	10 nF	50 ohm

SAS internal connector

Figure 20. Zero-length test load

Figure 21 shows an ISI loss example at 3.0 Gbps.

S21 (dB)
		Compliance interconnect magnitude response and
0		ISI loss example for 3.0 Gbps
ISI loss
> 3.9 dB
-10.9 dB		Sample compliance interconnect
0.3	1.5	Frequency (GHz)
		3.0

Figure 21. ISI loss example at 3.0 Gbps

Figure 22 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 22. ISI loss example at 1.5 Gbps

68 Barracuda ES.2 SAS Product Manual, Rev. E