Datasheet

Rev. 1.0 July 2008
DDR2 SDRAM
RDIMM
12 of 26
V
DDQ
V
IH
(AC) min
V
IH
(DC) min
V
REF
V
IL
(DC) max
V
IL
(AC) max
V
SS
< AC Input Test Signal Waveform >
V
SWING(MAX)
delta TRdelta TF
V
REF
- V
IL
(AC) max
delta TF
Falling Slew = Rising Slew =
V
IH
(AC) min - V
REF
delta TR
9.2 Operating Temperature Condition
Note :
1. Operating Temperature is the case surface temperature on the center/top side of the DRAM. For the measurement conditions, please refer to JESD51.2
standard.
2. At 85 - 95 °C operation temperature range, doubling refresh commands in frequency to a 32ms period ( tREFI=3.9 us ) is required, and to enter to self
refresh mode at this temperature range, an EMRS command is required to change internal refresh rate.
9.3 Input DC Logic Level
9.4 Input AC Logic Level
9.5 AC Input Test Conditions
Note :
1. Input waveform timing is referenced to the input signal crossing through the V
IH/IL
(AC) level applied to the device under test.
2. The input signal minimum slew rate is to be maintained over the range from V
REF
to V
IH
(AC) min for rising edges and the range from V
REF
to V
IL
(AC)
max for falling edges as shown in the below figure.
3. AC timings are referenced with input waveforms switching from V
IL
(AC) to V
IH
(AC) on the positive transitions and V
IH
(AC) to V
IL
(AC) on the negative
transitions.
Symbol Parameter Rating Units Notes
T
OPER
Operating Temperature 0 to 95 °C 1, 2
Symbol Parameter Min. Max. Units Notes
V
IH
(DC) DC input logic high V
REF
+ 0.125 V
DDQ
+ 0.3 V
V
IL
(DC) DC input logic low - 0.3 V
REF
- 0.125 V
Symbol Parameter
DDR2-400, DDR2-533 DDR2-667, DDR2-800
Units
Min. Max. Min. Max.
V
IH
(AC) AC input logic high V
REF
+ 0.250 - V
REF
+ 0.200 V
V
IL
(AC) AC input logic low - V
REF
- 0.250 V
REF
- 0.200 V
Symbol Condition Value Units Notes
V
REF
Input reference voltage 0.5 * V
DDQ
V1
V
SWING(MAX)
Input signal maximum peak to peak swing 1.0 V 1
SLEW Input signal minimum slew rate 1.0 V/ns 2, 3