Datasheet

Rev. 1.0 / Jul. 2012 37
Differential Input Cross Point Voltage
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 table below. The differential input cross point voltage VIX is measured from the actual
cross point of true and complement signals to the midlevel between of VDD and VSS
Vix Definition
Notes:
1. The relation between Vix Min/Max and VSEL/VSEH should satisfy following.
(VDD/2) + Vix (Min) - VSEL
 25mV 
VSEH - ((VDD/2) + Vix (Max))
 25mV
Cross point voltage for differential input signals (CK, DQS)
Symbol Parameter
DDR3-800, 1066, 1333, 1600 & 1866
Unit Notes
Min Max
V
IX
Differential Input Cross Point Voltage
relative to VDD/2 for CK,
CK
-150 150 mV 1
V
IX
Differential Input Cross Point Voltage
relative to VDD/2 for DQS,
DQS
-150 150 mV 1