PHY Lite for Parallel Interfaces Intel® FPGA IP User Guide

ID 683716
Date 7/15/2024
Public

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2.4.1.3.3. Differential Pin Configurations

Differential DQ output data pins can be configured into a maximum of 8 groups using x8 DQS trees, with a maximum of 5 differential DQ data pins per group except for the RZQ lane. The RZQ lane can have a maximum of 4 differential DQ data pins. For instance, using a single-ended ref_clk reserved on pin 36 or 37 (Lane 3) and using differential strobe pins, the maximum number of single-ended DQ output data pins in this 8-group configuration can be determined as follows:

LANES 0, 1, 2, 4, 5, 6, and 7 : 7 groups/lanes x 5 DQ pins = 35 DQ pins

LANE 3 : 1 group/lane x 3 DQ pins = 3 DQ pins

TOTAL : 38 DQ pins

Figure 24. Differential DQ Output Data Pin Configuration for 8 Groups

Differential DQ output data pins can also be configured into a maximum of 11 pins per group, with a maximum of 4 groups using x16 DQS trees. Using the same scenario of a single-ended ref_clk reserved on pin 36 or 37 (Lane 3) and using differential strobe pins, the maximum number of single-ended DQ output data pins in this 4-group configuration can be determined as follows:

LANES 0-1, 4-5, and 6-7 : 3 groups x 11 DQ pins = 33 DQ pins

LANES 2-3 : 1 group x 9 DQ pins = 9 DQ pins

TOTAL : 42 DQ pins

Figure 25. Differential DQ Output Data Pin Configuration for 4 Groups

Differential DQ input or bidirectional data pins cannot share the same lane as the RZQ pin. Thus, input or bidirectional data pins can be configured into a maximum of 7 groups using x8 DQS trees, with a maximum of 5 pins per group. Using the same scenario of a single-ended ref_clk reserved on pin 36 or 37 (Lane 3) and using differential strobe pins, the maximum number of differential DQ input or bidirectional data pins in this 7-group configuration can be determined as follows:

LANES 0, 1, 2, 4, 5, 6, and 7 : 7 groups/lanes x 5 DQ pins = 35 DQ pins

LANE 3 : 0 group/lane x 0 DQ pins = 0 DQ pins

TOTAL : 35 DQ pins

Figure 26. Differential DQ Input or Bidirectional Data Pin Configuration for 7 Groups

Differential input or bidirectional data pins can also be configured into a maximum of 4 groups using x16 DQS trees, with a maximum of 11 pins per group except for the RZQ lane, which cannot be shared with any input or bidirectional data pin. Using the same scenario of a single-ended ref_clk reserved on pin 36 or 37 (Lane 3) and using differential strobe pins, the maximum number of differential DQ input or bidirectional data pins in this 4-group configuration can be determined as follows:

LANES 0-1, 4-5, and 6-7 : 3 groups x 11 DQ pins = 33 DQ pins

LANE 2 : 1 group x 5 DQ pins = 5 DQ pins

LANE 3 : 0 group x 0 DQ pins = 0 DQ pins

Total : 38 DQ pins

Figure 27. Differential DQ Input or Bidirectional Data Pin Configuration for 4 Groups