2000 Fairchild Semiconductor Corporation
DS006434
www.fairchildsemi.com
August 1986
Revised March 2000
DM74LS393
Dual
4-
Bit
Bi
nary
Count
er
DM74LS393
Dual 4-Bit Binary Counter
General Description
Each of these monolithic circuits contains eight master-
slave flip-flops and additional gating to implement two indi-
vidual four-bit counters in a single package. The
DM74LS393 comprises two independent four-bit binary
counters each having a clear and a clock input. N-bit binary
counters can be implemented with each package providing
the capability of divide-by-256. The DM74LS393 has paral-
lel outputs from each counter stage so that any submultiple
of the input count frequency is available for system-timing
signals.
Features
s
Dual version of the popular DM74LS93
s
DM74LS393 dual 4-bit binary counter with individual
clocks
s
Direct clear for each 4-bit counter
s
Dual 4-bit versions can significantly improve system
densities by reducing counter package count by 50%
s
Typical maximum count frequency 35 MHz
s
Buffered outputs reduce possibility of collector commu-
tation
Ordering Code:
Devices also available in Tape and Reel. Specify by appending the suffix letter "X" to the ordering code.
Connection Diagram
Function Table
Counter Sequence (Each Counter)
H
=
HIGH Logic Level
L
=
LOW Logic Level
Order Number
Package Number
Package Description
DM74LS393M
M14A
14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-120, 0.150 Narrow
DM74LS373N
N14A
14-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Count
Outputs
Q
D
Q
C
Q
B
Q
A
0
L
L
L
L
1
L
L
L
H
2
L
L
H
L
3
L
L
H
H
4
L
H
L
L
5
L
H
L
H
6
L
H
H
L
7
L
H
H
H
8
H
L
L
L
9
H
L
L
H
10
H
L
H
L
11
H
L
H
H
12
H
H
L
L
13
H
H
L
H
14
H
H
H
L
15
H
H
H
H
3
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DM74LS393
Absolute Maximum Ratings
(Note 1)
Note 1: 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 2: C
L
=
15 pF, R
L
=
2 k
, T
A
=
25
C and V
CC
=
5V.
Note 3: C
L
=
50 pF, R
L
=
2 k
, T
A
=
25
C and V
CC
=
5V.
Note 4: The symbol (
) indicates that the falling edge of the clear pulse is used for reference.
Note 5: T
A
=
25
C, and V
CC
=
5V.
Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 6: All typicals are at V
CC
=
5V, T
A
=
25
C.
Note 7: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 8: I
CC
is measured with all outputs open, both CLEAR inputs grounded following momentary connection to 4.5V, and all other inputs grounded.
Supply Voltage
7V
Input Voltage
Clear
7V
A
5.5V
Operating Free Air Temperature Range
0
C to
+
70
C
Storage Temperature Range
-
65
C to
+
150
C
Symbol
Parameter
Min
Nom
Max
Units
V
CC
Supply Voltage
4.75
5
5.25
V
V
IH
HIGH Level Input Voltage
2
V
V
IL
LOW Level Input Voltage
0.8
V
I
OH
HIGH Level Output Current
-
0.4
mA
I
OL
LOW Level Output Current
8
mA
f
CLK
Clock Frequency (Note 2)
0
25
MHz
f
CLK
Clock Frequency (Note 3)
0
20
MHz
t
W
Pulse Width (Note 5)
A
20
ns
Clear HIGH
20
t
REL
Clear Release Time (Note 4)(Note 5)
25
ns
T
A
Free Air Operating Temperature
0
70
C
Symbol
Parameter
Conditions
Min
Typ
Max
Units
(Note 6)
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, V
I
=
7V
Clear
0.1
mA
Input Voltage
V
CC
=
Max, V
I
=
5.5V
A
0.2
I
IH
HIGH Level
V
CC
=
Max, V
I
=
2.7V
Clear
20
A
Input Current
A
40
I
IL
LOW
Level
V
CC
=
Max, V
I
=
0.4V
Clear
-
0.4
mA
Input Current
A
-
1.6
I
OS
Short Circuit Output Current
V
CC
=
Max (Note 7)
-
20
-
100
mA
I
CC
Supply Current
V
CC
=
Max (Note 8)
15
26
mA
5
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DM74LS393
Physical Dimensions
inches (millimeters) unless otherwise noted
14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-120, 0.150 Narrow
Package Number M14A
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