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DM74AS646 • DM74AS648
Absolute Maximum Ratings(Note 3)
Note 3: The “Absolute Maximum Ratings” are those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommended Operating Conditions” table will define the conditions
for actual device operation.
Recommended Operating Conditions
Note 4: The (↑) arrow indicates the positive edge of the Clock is used for reference.
Electrical Characteristics
over recommended operating free air temperature range. All typical values are measured at V
CC
= 5V, T
A
= 25°C.
Note 5: For I/O ports, the parameters I
IH
and I
IL
include the OFF-State current, I
OZH
and I
OZL
.
Supply Voltage 7V
Input Voltage
Control Inputs 7V
I/O Ports 5.5V
Operating Free Air Temperature Range 0
°C to +70°C
Storage Temperature Range
−65°C to +150°C
Typical
θ
JA
N Package 41.1°C/W
M Package 81.5
°C/W
Symbol Parameter Min Nom Max Units
V
CC
Supply Voltage 4.5 5 5.5 V
V
IH
HIGH Level Input Voltage 2 V
V
IL
LOW Level Input Voltage 0.8 V
I
OH
HIGH Level Output Current −15 mA
I
OL
LOW Level Output Current 48 mA
f
CLK
Clock Frequency 0 90 MHz
t
W
Width of Clock Pulse HIGH 5 ns
LOW 6 ns
t
SU
Data Setup Time (Note 4) 6↑ ns
t
H
Data Hold Time (Note 4) 0↑ ns
T
A
Free Air Operating Temperature 0 70 °C
Symbol Parameter Conditions Min Typ Max Units
V
IK
Input Clamp Voltage V
CC
= 4.5V, I
I
= −18 mA −1.2 V
V
OH
HIGH Level V
CC
= 4.5V, V
IL
= Max I
OH
= Max 2
Output Voltage V
IH
= Min I
OH
= −3 mA 2.4 3.2 V
V
CC
= 4.5V to 5.5V, I
OH
= −2 mA V
CC
− 2
V
OL
LOW Level V
CC
= 4.5V, V
IL
= Min
0.35 0.5 V
Output Voltage V
IH
= 2V, I
OL
= Max
I
I
Input Current @ Max V
CC
= 5.5V V
I
= 7V Control Inputs 0.1
mA
Input Voltage V
I
= 5.5V A or B Ports 0.1
I
IH
HIGH Level Input Current V
CC
= 5.5V, V
IH
= 2.7V Control Inputs 20
µA
(Note 5) A or B Ports 70
I
IL
LOW Level Input Current V
CC
= 5.5V, V
IL
= 0.4V Control Inputs −0.5
mA
(Note 5) A or B Ports −0.75
I
O
Output Drive Current V
CC
= 5.5V, V
O
= 2.25V −30 −112 mA
I
CC
Supply Current V
CC
= 5.5V Outputs HIGH 120 195
DM74AS646 Outputs LOW 130 211
Outputs Disabled 130 211
mA
Outputs HIGH 110 185
DM74AS648 Outputs LOW 120 195
Outputs Disabled 120 195
