User's Manual

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HW Design Guidelines
2.4. SGMII interface
The M18QF/M18QA Series modules integrate Ethernet MAC with SGMII interfaces with the
following key features:
IEEE 802.3 compliance
Full duplex at 1 Gbps
Half/full duplex for 10/100 Mbps
Supports VLAN tagging
Supports IEEE 1588, Precision Time Protocol (PTP)
Can be used to connect to external Ethernet PHYs such as AR8033 or to an
external switch
The following figure illustrates an example of the additional logic connection between the
modules and the Ethernet chip. Refer to ENG-46158, Rev 1.8 for electrical and timing
specifications.
Figure 2. SGMII circuit example
Layout suggestion:
Differential impedance:100 Ω
Space to other signals: > 3x line width
Lane-to-lane space: > 3x line width
Intra-lane mismatch: < 0.7 mm