APCPCWM_4828539:WP_0000005WP_0000005
A
P
C
P
C
W
M
_4828539:
W
P
_0000005W
P
_000000
5
Rev. 1.2 / Jul. 2010
18
Notes:
1. For CK,
CK
use VIH/VIL (ac) of ADD/CMD; for strobes (DQS, DQS, DQSL, DQSL, DQSU, DQSU) use VIH/VIL (ac)
of DQs.
2. VIH (ac)/VIL (ac) for DQs is based on VREFDQ; VIH (ac)/VIL (ac) for ADD/CMD is based on VREFCA; if a reduced
ac-high or ac-low level is used for a signal group, then the reduced level applies also here.
3. These values are not defined; however, the single-ended signals Ck, CK, DQS, DQS, DQSL, DQSL, DQSU, DQSU
need to be within the respective limits (VIH (dc) max, VIL (dc) min) for single-ended signals as well as the limita-
tions for overshoot and undershoot. Refer to “Overshoot and Undershoot Specifications” on page 25.
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 the 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
Single-ended levels for CK, DQS, DQSL, DQSU, CK, DQS, DQSL or DQSU
Symbol
Parameter
DDR3-800, 1066, 1333
Unit Notes
Min
Max
VSEH
Single-ended high level for strobes
(VDD / 2) + 0.175
Note 3
V
1,2
Single-ended high level for Ck, CK
(VDD /2) + 0.175
Note 3
V
1,2
VSEL
Single-ended low level for strobes
Note 3
(VDD / 2) = 0.175
V
1,2
Single-ended low level for CK, CK
Note 3
(VDD / 2) = 0.175
V
1,2
VDD
VSS
VDD/2
V
IX
V
IX
V
IX
CK, DQS
CK, DQS
B48614/178.104.2.80/2010-07-08 11:46