IBMN625404GT3B
IBMN625804GT3B
256Mb Double Data Rate Synchronous DRAM
Preliminary
17. An input setup and hold time derating table is used to increase t and t in the case where the input slew
IS
IH
rate is below 0.5 V/ns.
∆t
∆t
Input Slew Rate
0.5 V/ns
Unit
ps
Note
1, 2
1, 2
1, 2
IS
IH
0
0
0.4 V/ns
+ 50
+ 100
0
0
ps
0.3 V/ns
ps
1. Input slew rate is based on the lesser of the slew rates determined by either V
rising transitions.
to V
or V
to V , similarly for
IL (DC)
IH (AC)
IL (AC)
IH (DC)
2. These derating parameters may be guaranteed by design or tester characterization and are not necessarily tested on each
device.
18. An input setup and hold time derating table is used to increase t and t in the case where the I/O slew
DS
DH
rate is below 0.5 V/ns.
∆t
∆t
DH
Input Slew Rate
0.5 V/ns
Unit
ps
Note
1, 2
1, 2
1, 2
DS
0
0
0.4 V/ns
+ 75
+ 75
ps
0.3 V/ns
+ 150
+ 150
ps
1. I/O slew rate is based on the lesser of the slew rates determined by either V
rising transitions.
to V
or V
to V , similarly for
IL (DC)
IH (AC)
IL (AC)
IH (DC)
2. These derating parameters may be guaranteed by design or tester characterization and are not necessarily tested on each
device.
19. An I/O Delta Rise, Fall Derating table is used to increase t and t in the case where DQ, DM, and
DS
DH
DQS slew rates differ.
∆t
∆t
DH
Delta Rise and Fall Rate
0.0 ns/V
Unit
ps
Note
DS
1, 2,
3, 4
0
0
1, 2,
3, 4
0.25 ns/V
0.5 ns/V
+ 50
+ 50
ps
ps
1, 2,
3, 4
+ 100
+ 100
1. Input slew rate is based on the lesser of the slew rates determined by either V
rising transitions.
to V
or V
to V , similarly for
IL (DC)
IH (AC)
IL (AC)
IH (DC)
2. Input slew rate is based on the larger of AC to AC delta rise, fall rate and DC to DC delta rise, fall rate.
3. The delta rise, fall rate is calculated as: [1/(slew rate 1)] - [1/(slew rate 2)]
For example: slew rate 1 = 0.5 V/ns; slew rate 2 = 0.4 V/ns
Delta rise, fall = (1/0.5) - (1/0.4) [ns/V]
= -0.5 ns/V
Using the table above, this would result in an increase in t and t of 100 ps.
DS
DH
4. These derating parameters may be guaranteed by design or tester characterization and are not necessarily tested on each
device.
©IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
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