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DM74LS161A • DM74LS163A
DM74LS161A Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 4: All typicals are at V
CC
= 5V, T
A
= 25°C.
Note 5: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 6: I
CCH
is measured with the load HIGH, then again with the load LOW, with all other inputs HIGH and all outputs OPEN.
Note 7: I
CCL
is measured with the clock input HIGH, then again with the clock input LOW, with all other inputs LOW and all outputs OPEN.
DM74LS161A Switching Characteristics
at V
CC
= 5V and T
A
= 25°C
Symbol Parameter Conditions Min
Typ
Max Units
(Note 4)
V
I
Input Clamp Voltage V
CC
= Min, I
I
= −18 mA −1.5 V
V
OH
HIGH Level V
CC
= Min, I
OH
= Max
2.7 3.4 V
Output Voltage V
IL
= Max, V
IH
= Min
V
OL
LOW Level V
CC
= Min, I
OL
= Max
0.35 0.5
Output Voltage V
IL
= Max, V
IH
= Min V
I
OL
= 4 mA, V
CC
= Min 0.25 0.4
I
I
Input Current @ Max V
CC
= Max Enable T 0.2
Input Voltage V
I
= 7V Clock 0.2
mA
Load 0.2
Others 0.1
I
IH
HIGH Level V
CC
= Max Enable T 40
Input Current V
I
= 2.7V Clock 40
µA
Load 40
Others 20
I
IL
LOW Level V
CC
= Max Enable T −0.8
Input Current V
I
= 0.4V Clock −0.8
mA
Load −0.8
Others −0.4
I
OS
Short Circuit Output Current V
CC
= Max (Note 5) −20 −100 mA
I
CCH
Supply Current with Outputs HIGH V
CC
= Max (Note 6) 18 31 mA
I
CCL
Supply Current with Outputs LOW V
CC
= Max (Note 7) 19 32 mA
From (Input) R
L
= 2 kΩ
Symbol Parameter To (Output) C
L
= 15 pF C
L
= 50 pF Units
Min Max Min Max
f
MAX
Maximum Clock Frequency 25 20 MHz
t
PLH
Propagation Delay Time Clock to
25 30 ns
LOW-to-HIGH Level Output Ripple Carry
t
PHL
Propagation Delay Time Clock to
30 38 ns
HIGH-to-LOW Level Output Ripple Carry
t
PLH
Propagation Delay Time Clock to Any Q
22 27 ns
LOW-to-HIGH Level Output (Load HIGH)
t
PHL
Propagation Delay Time Clock to Any Q
27 38 ns
HIGH-to-LOW Level Output (Load HIGH)
t
PLH
Propagation Delay Time Clock to Any Q
24 30 ns
LOW-to-HIGH Level Output (Load LOW)
t
PHL
Propagation Delay Time Clock to Any Q
27 38 ns
HIGH-to-LOW Level Output (Load LOW)
t
PLH
Propagation Delay Time Enable T to
14 27 ns
LOW-to-HIGH Level Output Ripple Carry
t
PHL
Propagation Delay Time Enable T to
15 27 ns
HIGH-to-LOW Level Output Ripple Carry
t
PHL
Propagation Delay Time Clear to
28 45 ns
HIGH-to-LOW Level Output Any Q
