DIFF_TERM_ADV - 2024.1 English

Vivado Design Suite Properties Reference Guide (UG912)

Document ID
UG912
Release Date
2024-05-30
Version
2024.1 English

The advanced differential termination (DIFF_TERM_ADV) property is intended for use with UltraScale architecture only, and is used to enable or disable the built-in, 100Ω, differential termination for inputs or bidirectional ports. DIFF_TERM_ADV indicates a differential termination method should be used on differential input and bidirectional port buffers, and that the Vivado Design Suite should add on-chip termination to the port.

DIFF_TERM_ADV is only available for inputs and bidirectional ports and can only be used with the appropriate VCCO voltage. The VCCO of the I/O bank must be connected to 1.8V for HP I/O banks, and 2.5V for HR I/O banks to provide 100Ω of effective differential termination. Refer to the UltraScale Architecture SelectIO Resources User Guide (UG571) for more information.

Important: To support the migration of 7 series designs to UltraScale architecture, the Vivado tool. will automatically migrate the DIFF_TERM property to the DIFF_TERM_ADV property. However, in some cases this property is not supported, and should not be specified, or should be specified as “” (NULL) value.
Architecture Support
UltraScale devices.
Applicable Objects
  • Ports (get_ports)
    • Input or bidirectional ports connected to a differential input buffer
  • Applicable to objects using one of the following IOSTANDARDs:
    • LVDS, LVDS_25, MINI_LVDS_25, SUB_LVDS
    • PPDS_25
    • RSDS_25
    • SLVS_400_25, and SLVS_400_18
Values
TERM_100
Utilize the 100Ω on-chip differential termination.
TERM_NONE
Do not utilize the on-chip differential termination (default).
Note: The TERM_NONE value is the default value when the DIFF_TERM_ADV property is valid, such as for supported IOSTANDARDs and voltage levels. However, where it is not supported, it should not be specified and DIFF_TERM_ADV=TERM_NONE can result in a DRC violation. In these cases you can set the property to a NULL value using one of the following commands:
reset_proeprty DIFF_TERM_ADV [get_ports <port_name>]
-or-
set_property DIFF_TERM_ADV "" [get_ports <port_name>]

Syntax

Verilog Syntax

Not applicable

VHDL Syntax

Not applicable

XDC Syntax
set_property DIFF_TERM_ADV TERM_100 [get_ports <port_name>]

Where:

  • set_property DIFF_TERM_ADV can be assigned to input or bidirectional ports.
  • port_name is an input or bidirectional port connected to a differential buffer.

XDC Syntax Example:

# Enables differential termination on port named CLK_p 
set_property DIFF_TERM_ADV TERM_100 [get_ports CLK_p]

Affected Steps

  • I/O Planning
  • report_drc
  • report_ssn
  • report_power