UltraScale Architecture SelectIO Resources User Guide (UG571)

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1.14 English

The IOBUFDS_DIFF_OUT_DCIEN primitive shown in This Figure is available in the HP I/O banks. It has complementary differential outputs, an IBUFDISABLE port, and a DCITERMDISABLE port that can be used to manually disable the optional DCI on-die receiver termination features (uncalibrated or DCI). See DCI—Only Available in the HP I/O Banks and Uncalibrated Input Termination in I/O Banks for more details. TM and TS must be connected to the same input from the interconnect logic for this primitive to have the expected behavior that is specific to the UltraScale architecture.

Figure 1-37:      Differential Bidirectional Buffer with Complementary Outputs, Input Path Disable, and On-Die Input Termination Disable (IOBUFDS_DIFF_OUT_DCIEN)

X-Ref Target - Figure 1-37


If the I/O is using any on-die receiver termination features (uncalibrated or DCI), this primitive disables the termination legs whenever the DCITERMDISABLE signal is asserted High and the output buffer is 3-stated. When the output buffer is 3-stated (T = High), any on-die receiver termination (uncalibrated or DCI) is controlled by DCITERMDISABLE. When the output buffer is not 3-stated (T = Low), the input buffer and on-die receiver termination (uncalibrated or DCI) are disabled and the O output (to the internal logic) is forced to a logic-Low.


TIP:   The IBUFDISABLE feature is not supported with this primitive in the UltraScale architecture.