hys64t128020eu-3s-b2 Qimonda, hys64t128020eu-3s-b2 Datasheet - Page 26

• Manufacturer Part Number: hys64t128020eu-3s-b2
• Description: 240-pin Unbuffered Ddr2 Sdram Modules Udimm Sdram
• Manufacturer: Qimonda

11) MIN (
12) The
13) The Auto-Refresh command interval has be reduced to 3.9 µs when operating the DDR2 DRAM in a temperature range between 85 °C
14) 0 °C≤
15) 85 °C <
16) A maximum of eight Refresh commands can be posted to any given DDR2 SDRAM, meaning that the maximum absolute interval between
17) The
18) The maximum limit for the
19) Minimum
20) User can choose two different active power-down modes for additional power saving via MRS address bit A12. In “standard active power-
21) WR must be programmed to fulfill the minimum requirement for the
Rev. 1.01, 2008-01
10202006-L0SM-FEYT
be greater than the minimum specification limits for
(
parameters are verified by design and characterization, but not subject to production test.
and 95 °C.
any Refresh command and the next Refresh command is 9 x
performance (bus turnaround) degrades accordingly.
down mode” (MR, A12 = “0”) a fast power-down exit timing
power-down exit timing
up to the next integer value.
refers to the application clock period. WR refers to the WR parameter stored in the MRS.
t
HZ,
t
t
t
HZ
RPST
RRD
t
CL
T
,
CASE
T
,
t
RPST
timing parameter depends on the page size of the DRAM organization.
), or begins driving (
t
CASE
t
CH
WTR
) refers to the smaller of the actual clock low time and the actual clock high time as provided to the device (i.e. this value can
≤ 85 °C.
and
≤ 95 °C.
is two clocks when operating the DDR2-SDRAM at frequencies ≤ 200 ΜΗz.
t
LZ
,
t
RPRE
t
XARDS
t
parameters are referenced to a specific voltage level, which specify when the device output is no longer driving
WPST
t
t
DAL
LZ,
has to be satisfied.
parameter is not a device limit. The device operates with a greater value for this parameter, but system
t
= WR + (
RPRE
).
t
HZ
t
RP
and
/
t
CK
t
LZ
). For each of the terms, if not already an integer, round to the next highest integer.
transitions occur in the same access time windows as valid data transitions.These
t
CL
and
t
t
XARD
CH
t
REFI
).
26
can be used. In “low active power-down mode” (MR, A12 =”1”) a slow
.
t
WR
HYS[64/72]T[32/64/128]xxxEU-[25F/2.5/3/3S/3.7]-B2
Method for Calculating Transitions and Endpoint
timing parameter, where
Unbuffered DDR2 SDRAM Module
WR
MIN
[cycles] =
Internet Data Sheet
t
WR
(ns)/
FIGURE 3
t
CK
(ns) rounded
t
CK