DDR SDRAM 256Mb E-die (x4, x8)
Overshoot/Undershoot specification for Data, Strobe, and Mask Pins
Parameter
Maximum peak amplitude allowed for overshoot
Maximum peak amplitude allowed for undershoot
The area between the overshoot signal and VDD must be less than or equal to
The area between the undershoot signal and GND must be less than or equal to
DDR SDRAM
Specification
DDR333
TBD
TBD
TBD
TBD
DDR200/266
1.2 V
1.2 V
2.4 V-ns
2.4 V-ns
VDDQ
Overshoot
5
4
3
2
Volts (V)
1
0
-1
-2
-3
-4
-5
0 0.5 1.0 1.42 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 5.68 6.0 6.5 7.0
Tims(ns)
undershoot
Maximum Amplitude = 1.2V
GND
Area = 2.4V-ns
Maximum Amplitude = 1.2V
DQ/DM/DQS AC overshoot/Undershoot Definition
Rev. 1.3 April. 2005