NSC JM38510-30102BD, JM38510-30102BC, JM38510-30102SD, JM38510-30102SC Datasheet
TL/F/6373
54LS74/DM54LS74A/DM74LS74A Dual Positive-Edge-Triggered
D Flip-Flops with Preset, Clear and Complementary Outputs
June 1989
54LS74/DM54LS74A/DM74LS74A
Dual Positive-Edge-Triggered D Flip-Flops
with Preset, Clear and Complementary Outputs
General Description
This device contains two independent positive-edge-triggered D flip-flops with complementary outputs. The information on the D input is accepted by the flip-flops on the positive going edge of the clock pulse. The triggering occurs at a
voltage level and is not directly related to the transition time
of the rising edge of the clock. The data on the D input may
be changed while the clock is low or high without affecting
the outputs as long as the data setup and hold times are not
violated. A low logic level on the preset or clear inputs will
set or reset the outputs regardless of the logic levels of the
other inputs.
Features
Y
Alternate military/aerospace device (54LS74) is available. Contact a National Semiconductor Sales Office/
Distributor for specifications.
Connection Diagram
Dual-In-Line Package
TL/F/6373– 1
Order Number 54LS74DMQB, 54LS74FMQB, 54LS74LMQB,
DM54LS74AJ, DM54LS74AW, DM74LS74AM or DM74LS74AN
See NS Package Number E20A, J14A, M14A, N14A or W14B
Function Table
Inputs Outputs
PR CLR CLK D Q Q
LH XXHL
HL XXLH
LL XXH*H*
HH
u
HH L
HH
u
LL H
HH LXQ
0
Q
0
H
e
High Logic Level
X
e
Either Low or High Logic Level
L
e
Low Logic Level
u
e
Positive-going Transition
*
e
This configuration is nonstable; that is, it will not persist when either the preset
and/or clear inputs return to their inactive (high) level.
Q
0
e
The output logic level of Q before the indicated input conditions were established.
C
1995 National Semiconductor Corporation RRD-B30M105/Printed in U. S. A.
Absolute Maximum Ratings (Note)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.
Supply Voltage 7V
Input Voltage 7V
Operating Free Air Temperature Range
DM54LS and 54LS
b
55§Ctoa125§C
DM74LS 0
§
Ctoa70§C
Storage Temperature Range
b
65§Ctoa150§C
Note:
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’’
table are not guaranteed at the absolute maximum ratings.
The ‘‘Recommended Operating Conditions’’ table will define
the conditions for actual device operation.
Recommended Operating Conditions
Symbol Parameter
DM54LS74A DM74LS74A
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
f
CLK
Clock Frequency (Note 2) 0 25 0 25 MHz
f
CLK
Clock Frequency (Note 3) 0 20 0 20 MHz
t
W
Pulse Width Clock High 18 18
(Note 2)
Preset Low 15 15 ns
Clear Low 15 15
t
W
Pulse Width Clock High 25 25
(Note 3)
Preset Low 20 20 ns
Clear Low 20 20
t
SU
Setup Time (Notes 1 and 2) 20
u
20
u
ns
t
SU
Setup Time (Notes 1 and 3) 25
u
25
u
ns
t
H
Hold Time (Note 1 and 4) 0
u
0
u
ns
T
A
Free Air Operating Temperature
b
55 125 0 70
§
C
Note 1: The symbol (u) indicates the rising edge of the clock pulse is used for reference.
Note 2: C
L
e
15 pF, R
L
e
2kX,T
A
e
25§C, and V
CC
e
5V.
Note 3: C
L
e
50 pF, R
L
e
2kX,T
A
e
25§C, and V
CC
e
5V.
Note 4: T
A
e
25§C and V
CC
e
5V.
2
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