5 receiver characteristics – Seagate Cheetah 15K.5 SAS ST373455SS User Manual
Page 77
Cheetah 15K.5 SAS Product Manual, Rev. E
71
9.5.2.5
Receiver characteristics
The drive receiver is A.C. coupled. The receive network terminates the TxRx connection by a 100 ohm equiva-
lent impedance as specified in table 20.
The receiver operates within a BER of 10
-12
when a SAS signal with valid voltage and timing characteristics is
delivered to the compliance point from a 100 ohm source. The received SAS signal are considered valid if it
meets the voltage and timing limits specified in table 17.
Additionally the receiver operates within the BER objective when the signal at a receiving phy has the addi-
tional sinusoidal jitter present that is specified in table 19 and the common mode signal V
CM
over frequency
range F
CM
as specified in table 15. The jitter tolerance is shown in Figure 22 for all Rx compliance points in a
TxRx connection. The figure given assumes that any external interference occurs prior to the point at which the
test is applied. When testing the jitter tolerance capability of a receiver, the additional 0.1 UI of sinusoidal jitter
may be reduced by an amount proportional to the actual externally induced interference between the applica-
tion point of the test and the input to the receiving phy. The additional jitter reduces the eye opening in both
voltage and time.