74ls194a National Semiconductor Corporation, 74ls194a Datasheet - Page 3

• Manufacturer Part Number: 74ls194a
• Description: 4-bit Bidirectional Universal Shift Register
• Manufacturer: National Semiconductor Corporation

Switching Characteristics
Note 1 All typicals are at V
Note 2 Not more than one output should be shorted at a time and the duration should not exceed one second
Note 3 With all outputs open inputs A through D grounded and 4 5V applied to S0 S1 CLEAR and the serial inputs I
4 5V applied to CLOCK
Logic Diagram
Function Table
Symbol
f
t
t
t
MAX
PLH
PHL
PHL
H
u
a b c d
Q
Q
A0
An
Clear
e
e
H
H
H
H
H
H
H
L
Q
Q
High Level (steady state) L
Transition from low to high level
Maximum Clock
Frequency
Propagation Delay Time
Low to High Level Output
Propagation Delay Time
High to Low Level Output
Propagation Delay Time
High to Low Output
B0
Bn
e
Q
Q
The level of steady state input at inputs A B C or D respectively
C0
Cn
CC
S1
X
X
H
H
H
L
L
L
Parameter
Q
Q
Mode
e
D0
Dn
5V T
e
e
S0
X
X
H
H
H
L
L
L
The level of Q
The level of Q
A
e
25 C
Clock
u
u
u
u
u
X
L
X
e
Low Level (steady state) X
A
A
at V
Q
Q
Inputs
B
B
Left
H
X
X
X
X
X
L
X
Q
Q
CC
C
C
Serial
From (Input)
To (Output)
or Q
respectively before the most-recent
e
Clock to
Clock to
Clear to
5V and T
Any Q
Any Q
Any Q
Right
D
H
X
X
X
L
X
X
X
respectively before the indicated steady state input conditions were established
LS194A
A
3
e
A
X
X
a
X
X
X
X
X
e
Don’t Care (any input including transitions)
25 C (See Section 1 for Test Waveforms and Output Load)
Parallel
B
X
X
X
X
X
X
X
b
Min
30
C
C
X
X
X
c
X
X
X
X
L
54LS
e
15 pF
D
X
X
d
X
X
X
X
X
u
transition of the clock
Max
21
24
26
Q
Q
Q
Q
Q
H
L
a
L
A0
Bn
Bn
A0
A
Q
Q
Q
Q
Q
Q
Q
CC
L
b
Cn
Cn
Outputs
B0
An
An
B0
B
Min
20
is tested with momentary ground then
C
R
DM74LS
L
L
Q
Q
Q
Q
e
Q
Q
Q
e
L
c
C0
Bn
Bn
Dn
Dn
C0
C
50 pF
2 kX
Max
26
35
38
Q
Q
Q
Q
Q
H
L
d
L
D0
D0
Cn
Cn
D
TL F 6407 – 2
Units
MHz
ns
ns
ns