Справочник Пользователя для Hynix HMT325U7CFR8C-PBT0
Rev. 1.2 / Jul. 2013
24
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
Symbol
Parameter
DDR3-800, 1066, 1333, 1600, 1866
Unit Notes
Min
Max
V
IX
(CK)
Differential Input Cross Point Voltage
relative to VDD/2 for CK, CK
-150
150
mV
2
-175
175
mV
1
V
IX
(DQS)
Differential Input Cross Point Voltage
relative to VDD/2 for DQS, DQS
-150
150
mV
2
No4tes:
1. Extended range for V
IX
is only allowed for clock and if single-ended clock input signals CK and CK are monotonic
with a single-ended swing VSEL / VSEH of at least VDD/2 +/-250 mV, and when the differential slew rate of CK -
CK is larger than 3 V/ns.
CK is larger than 3 V/ns.
2. 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)