Datasheet

To guarantee tight setup and hold times as well as output skew parameters with respect to clock and strobe,
each cross point voltage of differential input signals (CK, CK
and DQS, DQS) must meet the requirements in
below table. The differential input cross point voltage VIX is measured from the actual cross point of true and
complement signal to the mid level between of VDD and VSS.
Cross point voltage for differential input signals ( CK, DQS )
NOTE :1. Extended range for VIX is only allowed for clock and if single-ended clock input signals CKand CK are mono-
tonic, have a single-ended swing VSEL / VSEH of at least VDD/2 +/- 250 mV, and the differential slew rate of
CK-CK
is larger than 3 V/ ns. Refer to the table of Cross point voltage for differential input signals (CK, DQS)
for VSEL and VSEH standard values.
Differential input slew rate definition
NOTE : The differential signal (i.e. CK - CK and DQS - DQS) must be linear between these thresholds.
Symbol Parameter Min. Max. Units Notes
VIX Differential Input Cross Point Voltage relative to VDD/2 for CK, CK
-150 150 mV
-175 175 mV 1
VIX Differential Input Cross Point Voltage relative to VDD/2 for DQS, DQS
-150 150 mV
Description
Measured
Defined by
From To
Differential input slew rate for rising edge ( CK-CK
and DQS-DQS ) VILdiff (max) VIHdiff (min)
VIHdiff (min) - VILdiff (max)
Delta TRdiff
Differential input slew rate for falling edge ( CK-CK
and DQS-DQS ) VIHdiff (min) VILdiff (max)
VIHdiff (min) - VILdiff (max)
Delta TFdiff
VIX Definition
V
DD
CK, DQS
V
DD
/2
CK, DQS
V
SS
V
IX
V
IX
V
IX
Differential Input Slew Rate definition for DQS,
DQS
, and CK, CK
V
IHdiffmin
0
V
ILdiffmax
delta TRdiff
delta TFdiff
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Rev.1.1 April 2017
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