Primitive: Differential Bidirectional Buffer With Input Buffer Disable and On-die Input
- PRIMITIVE_GROUP: I/O
- PRIMITIVE_SUBGROUP: BIDIR_BUFFER
- Families: UltraScale, UltraScale+
The IOBUFDS_INTERMDISABLE primitive is available in the HR I/O banks. It has an IBUFDISABLE port that can be used to disable the input buffer during periods when the buffer is not being used. The IOBUFDS_INTERMDISABLE primitive also has an INTERMDISABLE port that can be used to disable the optional on-die receiver termination feature. See the UltraScale Architecture SelectIO Resources User Guide (UG571), "Uncalibrated Input Termination in I/O Banks" for more details on this feature.
The IOBUFDS_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). The USE_IBUFDISABLE attribute must be set to TRUE and SIM_DEVICE to the appropriate value for this primitive to have the expected behavior that is specific to the architecture. If the I/O is using the on-die receiver termination feature, this primitive disables the termination legs whenever the INTERMDISABLE signal is asserted High and the output buffer is 3-stated. 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. When the output buffer is not 3-stated (T = Low), the input buffer and 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.
I/O attributes that do not impact the logic function of the component, such as IOSTANDARD, DIFF_TERM, and IBUF_LOW_PWR, should be supplied to the top-level port via an appropriate property. For details on applying such properties to the associated port, see the Vivado Design Suite Properties Reference Guide (UG912).
|I||Input||1||Input of OBUF. Connect to the logic driving the output port.|
|IBUFDISABLE||Input||1||Disables input path through the buffer and forces to a logic Low. This feature is generally used to reduce power at times when the I/O is idle for a period of time.|
|INTERMDISABLE||Input||1||Control to enable/disable on-chip input termination. This is generally used to reduce power in long periods of an idle state.|
|IO||Inout||1||Bidirectional diff_p port to be connected directly to top-level inout port.|
|IOB||Inout||1||Bidirectional diff_n port to be connected directly to top-level inout port.|
|O||Output||1||Output path of the buffer.|
|T||Input||1||3-state enable input signifying whether the buffer acts as an input or output.|
Design Entry Method
|IP and IP Integrator Catalog||No|
|SIM_DEVICE||STRING||"7SERIES", "ULTRASCALE"||"7SERIES"||Set the device version for simulation functionality.|
|USE_IBUFDISABLE||STRING||"TRUE", "FALSE"||"TRUE"||Set this attribute to "TRUE" to enable the IBUFDISABLE pin.|
VHDL Instantiation Template
Library UNISIM; use UNISIM.vcomponents.all;
-- IOBUFDS_INTERMDISABLE: Differential Bidirectional Buffer With Input Buffer Disable and On-die Input -- UltraScale -- Xilinx HDL Language Template, version 2021.2 IOBUFDS_INTERMDISABLE_inst : IOBUFDS_INTERMDISABLE generic map ( SIM_DEVICE => "ULTRASCALE", -- Set the device version for simulation functionality (ULTRASCALE) USE_IBUFDISABLE => "TRUE" -- Enable/Disable the IBUFDISABLE pin (FALSE, TRUE) ) port map ( O => O, -- 1-bit output: Buffer output I => I, -- 1-bit input: Buffer input IBUFDISABLE => IBUFDISABLE, -- 1-bit input: Buffer disable input, high=disable INTERMDISABLE => INTERMDISABLE, -- 1-bit input: Input Termination Disable IO => IO, -- 1-bit inout: Diff_p inout (connect directly to top-level port) IOB => IOB, -- 1-bit inout: Diff_n inout (connect directly to top-level port) T => T -- 1-bit input: 3-state enable input ); -- End of IOBUFDS_INTERMDISABLE_inst instantiation
Verilog Instantiation Template
// IOBUFDS_INTERMDISABLE: Differential Bidirectional Buffer With Input Buffer Disable and On-die Input // UltraScale // Xilinx HDL Language Template, version 2021.2 IOBUFDS_INTERMDISABLE #( .SIM_DEVICE("ULTRASCALE"), // Set the device version for simulation functionality (ULTRASCALE) .USE_IBUFDISABLE("TRUE") // Enable/Disable the IBUFDISABLE pin (FALSE, TRUE) ) IOBUFDS_INTERMDISABLE_inst ( .O(O), // 1-bit output: Buffer output .I(I), // 1-bit input: Buffer input .IBUFDISABLE(IBUFDISABLE), // 1-bit input: Buffer disable input, high=disable .INTERMDISABLE(INTERMDISABLE), // 1-bit input: Input Termination Disable .IO(IO), // 1-bit inout: Diff_p inout (connect directly to top-level port) .IOB(IOB), // 1-bit inout: Diff_n inout (connect directly to top-level port) .T(T) // 1-bit input: 3-state enable input ); // End of IOBUFDS_INTERMDISABLE_inst instantiation