IOBUF_INTERMDISABLE

UltraScale Architecture SelectIO Resources User Guide (UG571)

Document ID
UG571
Release Date
2022-08-31
Revision
1.14 English

The IOBUF_INTERMDISABLE primitive shown in This Figure is available in the HR I/O banks. It has an IBUFDISABLE port that can be used to disable the input buffer during periods that the buffer is not being used. The IOBUF_INTERMDISABLE primitive also has an INTERMDISABLE port that can be used to manually disable the optional on-die receiver termination feature. See Uncalibrated Input Termination in I/O Banks for more details.

Figure 1-32:      Bidirectional Buffer with Input Path Disable and On-Die Input Termination Disable (IOBUF_INTERMDISABLE)

X-Ref Target - Figure 1-32

X16092-bidi-buffer-w-input-path-disable-and-on-die-input-term-disable-iobuf_intermdisable.jpg

The IOBUF_INTERMDISABLE 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 and the output buffer is 3-stated (T = High). If the I/O is using the on-die receiver termination feature (uncalibrated), this primitive disables the termination legs whenever the INTERMDISABLE signal is asserted High and the output buffer is 3-stated (T = High). When the output buffer is 3-stated (T = High), the input buffer and any on-die receiver termination are controlled by IBUFDISABLE and INTERMDISABLE, respectively. 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. When the output buffer is not 3-stated (T = Low), the input buffer and any on-die receiver termination are disabled and the O output (to the internal logic) is forced to a logic-Low. These features can be combined to reduce power whenever the input is idle for a period of time.