9.5.2.5Receiver 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 10-12when 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 VCM over frequency range FCM as specified in table 15. The jitter tolerance is shown in Figure 19 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.

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Seagate ST3300656SS, ST3146356SS, ST3450856SS manual Receiver characteristics