Differential Termination Attribute

Versal Adaptive SoC SelectIO Resources Architecture Manual (AM010)

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In addition to calibrated impedance, a fixed precision 100Ω differential input impedance block is available in XP IOB input pairs to support LVDS15 and MIPI_DPHY. For both LVDS15 and MIPI_DPHY, the bank must be powered at the VCCO level (1.5V for LVDS15 or 1.2V for MPI_DPHY) to use the differential impedance block.

Differential termination can either be invoked using the DIFF_TERM or DIFF_TERM_ADV attributes. DIFF_TERM is used if specified in the instantiated primitive. DIFF_TERM_ADV is used if specified in the XDC constraints file. DIFF_TERM values specified in the instantiated primitive are translated to the corresponding DIFF_TERM_ADV setting in the XDC file. The allowed values for the DIFF_TERM attribute are TRUE or FALSE, which automatically maps to the DIFF_TERM_ADV attribute.

The DIFF_TERM_ADV attribute can be set to TERM_NONE (default) or TERM_100 to enable internal 100Ω termination. It uses the following syntax in the XDC file:
set_property DIFF_TERM_ADV [get_ports port_name]