XRS10L240 Datasheet, PDF (16/38 Pages) Exar Corporation – SERIAL ATA II: PORT MULTIPLIER / PORT SELECTOR

EXSTOR - 1 XRS10L240
SERIAL ATA II: PORT MULTIPLIER / PORT SELECTOR
REV. 1.05
4.0 ELECTRICAL SPECIFICATIONS
This section contains the electrical specifications for the XRS10L240.
4.1 Serial ATA Specifications
The XRS10L240 electrical transmit and receive specifications are outlined in this section. The XRS10L240 is
fully compliant to the Serial ATA II specification for Gen2i, Gen2x, Gen2m, Gen1i, Gen1x and Gen1m
variations at 3.0 and 1.5 Gbps.
4.1.1 Serial ATA Transmitter
A simplified version of the output circuit and test fixture for each of the 6 Serial ATA transmit output pairs on the
XRS10L240 is shown in Figure 11. The output differential pair is terminated to the supply VDD. The circuit is
designed to be AC coupled.
FIGURE 11. SERIAL ATA EQUIVALENT OUTPUT CIRCUIT
The XRS10L240 Serial ATA outputs include a simple one-tap equalizer, that is useful in driving longer printed
circuit traces and is a required component in second generation Serial ATA PHYs. This equalizer pre-
emphasizes the output signal whenever there is a data transition. The amount of pre-emphasis can vary
between 0 and 45.5%, and is configured via MDIO register settings. Note that pre-emphasis doesn't increase
the overall swing, but instead reduces the output amplitude when there is no transition.
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