DDR SDRAM 256Mb E-die (x4, x8)
DDR SDRAM
AC Operating Conditions
Parameter/Condition
Symbol
VIH(AC)
VIL(AC)
VID(AC)
Min
Max-10
Unit
V
Note
Input High (Logic 1) Voltage, DQ, DQS and DM signals
Input Low (Logic 0) Voltage, DQ, DQS and DM signals.
Input Differential Voltage, CK and /CK inputs
VREF + 0.31
VREF - 0.31
VDDQ+0.6
V
0.7
V
1
2
Input Crossing Point Voltage, CK and /CK inputs
VIX(AC) 0.5*VDDQ-0.2 0.5*VDDQ+0.2
V
Notes :
1. VID is the magnitude of the difference between the input level on CK and the input level on /CK.
2. The value of VIX is expected to equal 0.5*VDDQ of the transmitting device and must track variations in the dc level of the same.
AC Overshoot/Undershoot specification for Address and Control Pins
Parameter
Specification
DDR400
1.5V
Maximum peak amplitude allowed for overshoot
Maximum peak amplitude allowed for undershoot
1.5V
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
4.5V-ns
4.5V-ns
VDD
Overshoot
5
4
3
Maximum Amplitude = 1.5V
2
Area = 4.5V-ns
1
0
-1
-2
Maximum Amplitude = 1.5V
GND
-3
-4
-5
0
0.6875
0.5 1.0
1.5
2.5
3.5
4.5
5.5
6.3125
6.0 6.5
undershoot
7.0
2.0
3.0
4.0
5.0
Tims(ns)
AC overshoot/Undershoot Definition
Rev. 1.1 September. 2003
SAMSUNG [ SAMSUNG ]
