w9425g8dh Winbond Electronics Corp America, w9425g8dh Datasheet - Page 29

• Manufacturer Part Number: w9425g8dh
• Description: 8m ? 4 Banks ? 8 Bits Ddr Sdram
• Manufacturer: Winbond Electronics Corp America

Notes:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10) Transition times are measured between V
(11) IF the result of nominal calculation with regard to t
(12) V
(13) V
(14) V
(15) Refer to the figure below.
(16) t
(17) A maximum of eight AUTO REFRESH commands can be posted to any given DDR SDRAM device.
(18) t
Conditions outside the limits listed under “Absolute Maximum Ratings” may cause permanent damage to the device.
All voltages are referenced to V
Peak to peak AC noise on V
V
V
The values of I
The values of I
These parameters depend on the cycle rate and these values are measured at a cycle rate with the minimum values
of t
V
equal to V
These parameters depend on the output loading. Specified values are obtained with the output open.
slope.
the nearest decimal place.
(i.e., T
AC
DAL
OH
OH
TT
X
ID
ISO
CK
is the differential clock cross point voltage where input timing measurement is referenced.
and t
is magnitude of the difference between CLK input level and CLK input level.
is not applied directly to the device. V
= 1.95V, V
= 1.9V, V
= (t
means {V
and t
DQSS
0 V Differential
WR
DQSCK
REF
/t
RC
= 0.75 × t
CK
.
OL
and must track variations in the DC level of V
V
) + (t
ICK
OH(DC)
OL(DC)
OL
depend on the clock jitter. These timing are measured at stable clock.
ID(AC)
CLK
CLK
V
V
= 0.4V
V
ISO
SS
(CLK)+V
= 0.35V
SS
RP
V
CK
is based on V
/t
is based on V
ICK
CK
, t
V
X
)
CK
ICK
REF
= 7.5 nS, 0.75 × 7.5 nS = 5.625 nS is rounded up to 5.6 nS.)
( CLK )}/2.
SS
may not exceed ± 2% V
, V
DDQ
DDQ
V
ISO(min)
SSQ.(
V
V
= 2.3V and V
ICK
= 2.3V and V
X
TT
2.6V ± 0.1V for DDR400
IH min(AC)
is a system supply for signal termination resistors is expected to be set
CK
- 29 -
and V
TT
TT
contains more than one decimal place, the result is rounded up to
V
X
= 1.11V.
= 1.19V.
REF(DC).
IL max(AC)
REF
.
)
V
.Transition (rise and fall) of input signals have a fixed
ISO(max)
V
ICK
Publication Release Date: Nov. 20
V
X
V
ICK
V
X
V
ID(AC)
Revision A4
,
2007