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EM484M1644VTA
Note 5.2: AC characteristics assumed input rise and fall time (tr & tf) = 1ns.
If tr & tf is longer than 1ns, transient time compensation should be considered,
i.e., following compensation should be added to the parameter.
For example:
tIS : tr/2 (CLK rising edge )+ tT/2(tf for /cas/ras/we..start edge; tr or tf for address/data pin)-1ns
tIH : tr/2 (CLK rising edge )+ tT/2(tr for /cas/ras/we..end edge; tr or tf for address/data pin)-1ns
Note 5.3: tHZ defines the time at which the output achieve the open circuit condition and is not referenced
to output voltage levels.
AC Operating Test Characteristics (Continued)
(VDD=3.3V±0.3V, TA=0°C ~70°C/TA=-25°C ~ +85°C for extended grade)
-6
-7
Symbol
tRC
Parameter
Units
ns
Min. Max. Min. Max.
ACTIVE to ACTIVE Command
Period (Note 6)
60
40
18
18
12
1
62
42
18
18
14
1
ACTIVE to PRECHARGE
Command Period (Note 6)
tRAS
tRP
100k
100k
ns
PRECHARGE to ACTIVE
Command Period (Note 6)
ns
ACTIVE to READ/WRITE Delay
Time (Note 6)
tRCD
tRRD
tCCD
ns
ACTIVE(one) to ACTIVE(another)
Command (Note 6)
ns
READ/WRITE Command to
READ/WRITE Command
CLK
Date-in to PRECHARGE
Command
tDPL
tBDL
tROH
tREF
2
2
CLK
CLK
Date-in to BURST Stop Command
1
3
1
3
2
Data-out to High
Impedance from
PRECHARGE Command
CL=3
CL=2
CLK
ms
Refresh Time (4,096 cycle)
64
64
* All voltages referenced to VSS.
Note 6: These parameters account for the number of clock cycles and depend on the operating frequency
of the clock, as follows:
The number of clock cycles = Specified value of timing/clock period (Count Fractions as a whole
number)
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