EM44DM1688LBB
AC Operating Test Characteristics
(VDD=1.8V±0.1V)
-187 (DDR2-1066)
-25 (DDR2-800)
Units
Symbol
Parameter
Min.
Max.
Min.
Max.
tAC
tDQSCK
tCL,tCH
tCK
DQ output access from CLK,/CLK
DQS output access from CLK,/CLK
CL low/high level width
-350
-350
0.48
1.875
50
350
350
0.52
8
-400
-350
0.48
2.5
400
350
0.52
8
ps
ps
tCK
ns
ps
ps
Clock Cycle Time
tDS
DQ and DM setup time
-
50
-
tDH
DQ and DM hold time
75
-
125
-
DQ and DM input pulse width for each
input
tDIPW
tHZ
0.35
-
0.35
-
tCK
ns
tAC
tAC
Data out high impedance time from
CLK,/CLK
-
-
(max)
(max)
2*tAC
tAC
2*tAC
tAC
tLZ (DQ)
DQ low impedance time from CLK,/CLK
ns
ns
(min)
(max)
(min)
(max)
tAC
tAC
tAC
tAC
DQS,/DQS low impedance time from
CLK,/CLK
tLZ (DQS)
(min)
(max)
(min)
(max)
tDQSQ
tQHS
DQS-DQ skew for associated DQ signal
Data hold skew factor
-
175
-
200
ps
ps
-
250
-
300
Write command to first latching DQS
transition
tDQSS
-0.25
0.25
-0.25
0.25
tCK
tDQSL,tDQSH DQS Low/High input pulse width
0.35
0.20
2
-
0.35
0.20
2
-
tCK
tCK
tCK
ns
tCK
tCK
tDSL,tDSH
tMRD
DQS input valid window
Mode Register Set command cycle time
Write Preamble setup time
Write Preamble
-
-
-
-
-
-
tWPRES
tWPRE
tWPST
0
0
0.35
0.4
-
0.35
0.4
-
Write Postamble
0.6
0.6
Address/control input setup time (fast
slew rate)
tIS
0.175
-
0.20
-
ns
Address/control input hold time
(fast slew rate)
tIH
0.25
0.9
-
0.275
0.9
-
ns
tRPRE
Read Preamble
1.1
1.1
tCK
Nov. 2011
12/29
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