Datasheet
’LS157 Switching Characteristics
at V
CC
e
5V and T
A
e
25
§
C (See Section 1 for Test Waveforms and Output Load)
From (Input)
R
L
e
2kX
Symbol Parameter
To (Output)
C
L
e
15 pF C
L
e
50 pF Units
Min Max Min Max
t
PLH
Propagation Delay Time Data
14 18 ns
Low to High Level Output to Y
t
PHL
Propagation Delay Time Data
14 23 ns
High to Low Level Output to Y
t
PLH
Propagation Delay Time Strobe
20 24 ns
Low to High Level Output to Y
t
PHL
Propagation Delay Time Strobe
21 30 ns
High to Low Level Output to Y
t
PLH
Propagation Delay Time Select
23 28 ns
Low to High Level Output to Y
t
PHL
Propagation Delay Time Select
27 32 ns
High to Low Level Output to Y
Recommended Operating Conditions
Symbol Parameter
DM54LS158 DM74LS158
Units
Min Nom Max Min Nom Max
V
CC
Supply Voltage 4.5 5 5.5 4.75 5 5.25 V
V
IH
High Level Input Voltage 2 2 V
V
IL
Low Level Input Voltage 0.7 0.8 V
I
OH
High Level Output Current
b
0.4
b
0.4 mA
I
OL
Low Level Output Current 4 8 mA
T
A
Free Air Operating Temperature
b
55 125 0 70
§
C
’LS158 Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Symbol Parameter Conditions Min
Typ
Max Units
(Note 1)
V
I
Input Clamp Voltage V
CC
e
Min, I
I
eb
18 mA
b
1.5 V
V
OH
High Level Output V
CC
e
Min, I
OH
e
Max DM54 2.5 3.4
V
Voltage V
IL
e
Max, V
IH
e
Min
DM74 2.7 3.4
V
OL
Low Level Output V
CC
e
Min, I
OL
e
Max DM54 0.25 0.4
Voltage V
IL
e
Max, V
IH
e
Min
DM74 0.35 0.5 V
I
OL
e
4 mA, V
CC
e
Min DM74 0.25 0.4
I
I
Input Current
@
Max V
CC
e
Max S or G 0.2
mA
Input Voltage V
I
e
7V
AorB 0.1
I
IH
High Level Input V
CC
e
Max S or G 40
mA
Current V
I
e
2.7V
AorB 20
I
IL
Low Level Input V
CC
e
Max SorG
b
0.8
mA
Current V
I
e
0.4V
AorB
b
0.4
I
OS
Short Circuit V
CC
e
Max DM54
b
20
b
100
mA
Output Current (Note 2)
DM74
b
20
b
100
I
CC
Supply Current V
CC
e
Max (Note 3) 4.8 8 mA
Note 1: All typicals are at V
CC
e
5V, T
A
e
25
§
C.
Note 2: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 3: I
CC
is measured with 4.5V applied to all inputs and all outputs open.
3
Obsolete