Teledyne LeCroy QPHY-LPDDR2 - Manual (Page 44)

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QPHY-LPDDR2-OM-G Rev B
Figure 24. Data output (read) timing [JESD208-2B figure 23]
tQHS, DQ hold skew factor
This measures DQ at VIH(dc) or VIL(dc) to DQS at VREF
tQH, DQ/DQS Output Hold Time From DQS
This measures the timing from DQS at VREF to DQ at VIH(dc) (rising edge) or VIL(dc) (falling edge).
tQH = tQHP - tQHS
tDQSCK, DQS Output Access Time from CK/CK #
Time from CK at VREF level to DQS at VREF level.
Figure 25. Burst read operation [JESD209-2D figure 25]
This is a measure similar to tDQSS but on the Read.