Timing Constraint Rules for QDR-IV Signals

Versal Adaptive SoC PCB Design User Guide (UG863)

Document ID
UG863
Release Date
2024-04-01
Revision
1.8 English

The timing constraints are defined in the following tables for various signal groups and their targets, similar to how they would be entered into PCB layout software tools. Adaptive SoC package delays should always be included for purposes of determining skews.

Table 1. Skew Constraint Rules for 2x18 (36-bit) QDR-IV Signals 1
Skew Constraint Pin Pair Set Minimum (ps) Maximum (ps) Group Target
Address to Clock Adaptive SoC to QDR-IV device –6 +6

A[21:0]

AP

AINV

CFG_N

LBK0_N

LBK1_N

LDA_N

LDB_N

RWA_N

RWB_N

CK_P
Data to DKA0 Adaptive SoC to QDR-IV device –5 +5 DQA[8:0] DKA_P0
Data to DKA1 Adaptive SoC to QDR-IV device –5 +5 DQA[17:9] DKA_P1
Data to DKB0 Adaptive SoC to QDR-IV device –5 +5 DQB[8:0] DKB_P0
Data to DKB1 Adaptive SoC to QDR-IV device –5 +5 DQB[17:9] DKB_P1
Data to QKA0 Adaptive SoC to QDR-IV device –5 +5

DQA[8:0]

QVLDA[0]

QKA_P0
Data to QKA1 Adaptive SoC to QDR-IV device –5 +5

DQA[17:9]

QVLDA[1]

QKA_P1
Data to QKB0 Adaptive SoC to QDR-IV device –5 +5

DQB[8:0]

QVLDB[0]

QKB_P0
Data to QKB1 Adaptive SoC to QDR-IV device –5 +5

DQB[17:9]

QVLDB[1]

QKB_P1
DK to CK Adaptive SoC to QDR-IV device 0 +50 DKA0_P

DKA1_P

DKB0_P

DKB1_P

CK_P
QK to CK Adaptive SoC to QDR-IV device 0 +50 QKA0_P

QKA1_P

QKB0_P

QKB1_P

CK_P
Clock 2 Adaptive SoC to QDR-IV device 0 2

CK_P

CK_N

-
DKA0 2 Adaptive SoC to QDR-IV device 0 2

DKA0_P

DKA0_N

DKA1 2 Adaptive SoC to QDR-IV device 0 2

DKA1_P

DKA1_N

DKB0 2 Adaptive SoC to QDR-IV device 0 2

DKB0_P

DKB0_N

DKB1 2 Adaptive SoC to QDR-IV device 0 2

DKB1_P

DKB1_N

QKA0 2 Adaptive SoC to QDR-IV device 0 2

QKA0_P

QKA0_N

QKA1 2 Adaptive SoC to QDR-IV device 0 2

QKA1_P

QKA1_N

QKB0 2 Adaptive SoC to QDR-IV device 0 2

QKB0_P

QKB0_N

QKB1 2 Adaptive SoC to QDR-IV device 0 2

QKB1_P

QKB1_N

  1. Include adaptive SoC package delays for all skew calculations.
  2. It does not matter which signal is faster or slower, but the difference in time between the two should be no longer than specified.
Table 2. Skew Constraint Rules for 2x36 (72-bit) QDR-IV Signals 1
Skew Constraint Pin Pair Set Minimum (ps) Maximum (ps) Group Target
Address to Clock Adaptive SoC to QDR-IV device –6 +6

A[20:0]

AP

AINV

CFG_N

LBK0_N

LBK1_N

LDA_N

LDB_N

RWA_N

RWB_N

CK_P
Data to DKA0 Adaptive SoC to QDR-IV device –5 +5 DQA[17:0] DKA_P0
Data to DKA1 Adaptive SoC to QDR-IV device –5 +5 DQA[35:18] DKA_P1
Data to DKB0 Adaptive SoC to QDR-IV device –5 +5 DQB[17:0] DKB_P0
Data to DKB1 Adaptive SoC to QDR-IV device –5 +5 DQB[35:18] DKB_P1
Data to QKA0 Adaptive SoC to QDR-IV device –5 +5

DQA[17:0]

QVLDA[0]

QKA_P0
Data to QKA1 Adaptive SoC to QDR-IV device –5 +5

DQA[35:18]

QVLDA[1]

QKA_P1
Data to QKB0 Adaptive SoC to QDR-IV device –5 +5

DQB[17:0]

QVLDB[0]

QKB_P0
Data to QKB1 Adaptive SoC to QDR-IV device –5 +5

DQB[35:18]

QVLDB[1]

QKB_P1
DK to CK Adaptive SoC to QDR-IV device 0 +50 DKA0_P

DKA1_P

DKB0_P

DKB1_P

CK_P
QK to CK Adaptive SoC to QDR-IV device 0 +50 QKA0_P

QKA1_P

QKB0_P

QKB1_P

CK_P
Clock 2 Adaptive SoC to QDR-IV device 0 2

CK_P

CK_N

-
DKA0 2 Adaptive SoC to QDR-IV device 0 2

DKA0_P

DKA0_N

DKA1 2 Adaptive SoC to QDR-IV device 0 2

DKA1_P

DKA1_N

DKB0 2 Adaptive SoC to QDR-IV device 0 2

DKB0_P

DKB0_N

DKB1 2 Adaptive SoC to QDR-IV device 0 2

DKB1_P

DKB1_N

QKA0 2 Adaptive SoC to QDR-IV device 0 2

QKA0_P

QKA0_N

QKA1 2 Adaptive SoC to QDR-IV device 0 2

QKA1_P

QKA1_N

QKB0 2 Adaptive SoC to QDR-IV device 0 2

QKB0_P

QKB0_N

QKB1 2 Adaptive SoC to QDR-IV device 0 2

QKB1_P

QKB1_N

  1. Include adaptive SoC package delays for all skew calculations.
  2. It does not matter which signal is faster or slower, but the difference in time between the two should be no longer than specified.