XAUI v12.3 Product Guide
93
PG053 April 6, 2016
Chapter 6:
Design Considerations
A 156.25 MHz clock is derived from the transceiver TXOUTCLK port inside the core, and
used as the clock for the datapath logic of the XAUI core. This clock should be used for user
logic connecting to the core, using the clk156_out port; however, it cannot be used as a
clock source for the user logic of a different XAUI core, due to problems of phase alignment.
For more information about UltraScale device transceiver clock distribution, see the
UltraScale Architecture GTH Transceivers User Guide
.
UltraScale Device GTY Transceivers
A single IBUFDS_GTE3 module is used to feed the reference clock to the GTYE3_COMMON
transceiver. The IBUFDS_GTE3 is included in the Shared Logic level of hierarchy and so can
be included either in the example design or alternatively inside the core. See
and
respectively for the shared logic to be included in the example design or in the
core.
X-Ref Target - Figure 6-4
Figure 6
‐
4:
Clock Scheme for Internal Client-Side Interface UltraScale Architecture GTH
Transceiver Shared Logic in Core
Shareable logic
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