Datasheet

Rev. 1.0 July 2008
DDR2 SDRAM
RDIMM
11 of 26
Note : There is no specific device V
DD
supply voltage requirement for SSTL-1.8 compliance. However under all conditions V
DDQ
must be less than or equal
to V
DD
.
1. The value of V
REF
may be selected by the user to provide optimum noise margin in the system. Typically the value of V
REF
is expected to be about 0.5
x V
DDQ
of the transmitting device and V
REF
is expected to track variations in V
DDQ
.
2. Peak to peak AC noise on V
REF
may not exceed +/-2% V
REF
(DC).
3. V
TT
of transmitting device must track V
REF
of receiving device.
4. AC parameters are measured with V
DD
, V
DDQ
and V
DDL
tied together.
Symbol Parameter
Rating
Units Notes
Min. Typ. Max.
V
DD
Supply Voltage 1.7 1.8 1.9 V
V
DDL
Supply Voltage for DLL 1.7 1.8 1.9 V 4
V
DDQ
Supply Voltage for Output 1.7 1.8 1.9 V 4
V
REF
Input Reference Voltage 0.49*V
DDQ
0.50*V
DDQ
0.51*V
DDQ
mV 1,2
V
TT
Termination Voltage V
REF
-0.04 V
REF
V
REF
+0.04 V 3
Note :
1. Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Exposure to absolute maximum rating conditions for extended periods may affect reliability.
2. Storage Temperature is the case surface temperature on the center/top side of the DRAM. For the measurement conditions, please refer to JESD51-2
standard.
Symbol Parameter Rating Units Notes
V
DD
Voltage on V
DD
pin relative to V
SS
- 1.0 V ~ 2.3 V V 1
V
DDQ
Voltage on V
DDQ
pin relative to V
SS
- 0.5 V ~ 2.3 V V 1
V
DDL
Voltage on V
DDL
pin relative to V
SS
- 0.5 V ~ 2.3 V V 1
V
IN,
V
OUT
Voltage on any pin relative to V
SS
- 0.5 V ~ 2.3 V V 1
T
STG
Storage Temperature -55 to +100 °C 1, 2
9.0 AC & DC Operating Conditions
8.0 Absolute Maximum DC Ratings
9.1 Recommended DC Operating Conditions (SSTL - 1.8)