The IBUF_IBUFDISABLE primitive shown in This Figure is an input buffer with a disable port that can be used as an additional power saving feature for periods when the input is not used.
The IBUF_IBUFDISABLE primitive can disable the input buffer and force the O output to the internal logic to a logic-Low when the IBUFDISABLE signal is asserted High. The USE_IBUFDISABLE attribute must be set to TRUE, the IBUFDISABLE port must be controlled, and SIM_DEVICE set to ULTRASCALE for this primitive to have the expected behavior that is specific to the UltraScale architecture. This feature can be used to reduce power at times when the I/O is idle. Input buffers that use the VREF power rail (such as SSTL and HSTL) benefit the most from the IBUFDISABLE signal being set to a logic-High because they tend to have higher static power consumption than the non-VREF standards such as LVCMOS and LVTTL.