DDR SDRAM 256Mb E-die (x4, x8)
DDR SDRAM
System Characteristics for DDR SDRAM
The following specification parameters are required in systems using DDR400 devices to ensure proper system perfor-
mance. these characteristics are for system simulation purposes and are guaranteed by design.
Table 1 : Input Slew Rate for DQ, DQS, and DM
AC CHARACTERISTICS
DDR400
PARAMETER
SYMBOL
DCSLEW
MIN
0.5
MAX
4.0
Units
V/ns
Notes
a, k
DQ/DM/DQS input slew rate measured between
VIH(DC), VIL(DC) and VIL(DC), VIH(DC)
Table 2 : Input Setup & Hold Time Derating for Slew Rate
Input Slew Rate
0.5 V/ns
tIS
0
tIH
0
Units
ps
Notes
h
h
h
0.4 V/ns
+50
+100
0
ps
0.3 V/ns
0
ps
Table 3 : Input/Output Setup & Hold Time Derating for Slew Rate
Input Slew Rate
0.5 V/ns
tDS
0
tDH
0
Units
ps
Notes
j
j
j
0.4 V/ns
+75
+150
+75
+150
ps
0.3 V/ns
ps
Table 4 : Input/Output Setup & Hold Derating for Rise/Fall Delta Slew Rate
Delta Slew Rate
+/- 0.0 V/ns
tDS
0
tDH
0
Units
ps
Notes
i
i
i
+/- 0.25 V/ns
+/- 0.5 V/ns
+50
+100
+50
+100
ps
ps
Table 5 : Output Slew Rate Characteristice (X8 Devices only)
Typical Range
(V/ns)
Minimum
(V/ns)
Maximum
(V/ns)
Slew Rate Characteristic
Notes
Pullup Slew Rate
Pulldown slew
1.2 ~ 2.5
1.2 ~ 2.5
1.0
1.0
4.5
4.5
a,c,d,f,g
b,c,d,f,g
Table 6 : Output Slew Rate Characteristice (X16 Devices only)
Typical Range
(V/ns)
Minimum
(V/ns)
Maximum
(V/ns)
Slew Rate Characteristic
Notes
Pullup Slew Rate
Pulldown slew
1.2 ~ 2.5
1.2 ~ 2.5
0.7
0.7
5.0
5.0
a,c,d,f,g
b,c,d,f,g
Table 7 : Output Slew Rate Matching Ratio Characteristics
AC CHARACTERISTICS DDR400
PARAMETER
Output Slew Rate Matching Ratio (Pullup to Pulldown)
MIN
-
MAX
-
Notes
e,k
Rev. 1.1 September. 2003