MOTOROLA SN74LS42D

SN54/74LS42
ONE-OF-TEN DECODER
The LSTTL / MSI SN54 / 74LS42 is a Multipurpose Decoder designed to accept four BCD inputs and provide ten mutually exclusive outputs. The LS42
is fabricated with the Schottky barrier diode process for high speed and is
completely compatible with all Motorola TTL families.
•
•
•
•
ONE-OF-TEN DECODER
Multifunction Capability
Mutually Exclusive Outputs
Demultiplexing Capability
Input Clamp Diodes Limit High Speed Termination Effects
LOW POWER SCHOTTKY
CONNECTION DIAGRAM DIP (TOP VIEW)
A0
15
VCC
16
A1
14
A2
13
A3
12
9
8
7
11
10
9
J SUFFIX
CERAMIC
CASE 620-09
16
1
NOTE:
The Flatpak version has the
same pinouts (Connection
Diagram) as the Dual In-Line
Package.
1
2
3
4
5
6
7
8
0
1
2
3
4
5
6
GND
N SUFFIX
PLASTIC
CASE 648-08
16
1
PIN NAMES
LOADING (Note a)
HIGH
A0 – A3
0 to 9
Address Inputs
Outputs, Active LOW (Note b)
D SUFFIX
SOIC
CASE 751B-03
LOW
0.5 U.L.
10 U.L.
16
0.25 U.L.
5(2.5) U.L.
1
NOTES:
a) 1 TTL Unit Load (U.L.) = 40 µA HIGH/1.6 mA LOW.
b) The Output LOW drive factor is 2.5 U.L. for Military (54) and 5 U.L. for Commercial (74)
Temperature Ranges.
ORDERING INFORMATION
SN54LSXXJ
SN74LSXXN
SN74LSXXD
Ceramic
Plastic
SOIC
LOGIC DIAGRAM
A0
A1
15
A2
LOGIC SYMBOL
A3
13
14
12
15
14
13
12
A0
A1
A2
A3
0 1 2 3 4 5 6 7 8 9
1
0
3
2
1
2
4
3
6
5
4
5
7
6
9
7
10
8
11
9
VCC = PIN 16
GND = PIN 8
= PIN NUMBERS
FAST AND LS TTL DATA
5-53
1 2 3 4 5 6 7 9 10 11
VCC = PIN 16
GND = PIN 8
SN54/74LS42
FUNCTIONAL DESCRIPTION
to the inputs.
The most significant input A3 produces a useful inhibit function when the LS42 is used as a one-of-eight decoder. The A3
input can also be used as the Data input in an 8-output
demultiplexer application.
The LS42 decoder accepts four active HIGH BCD inputs
and provides ten mutually exclusive active LOW outputs, as
shown by logic symbol or diagram. The active LOW outputs
facilitate addressing other MSI units with LOW input enables.
The logic design of the LS42 ensures that all outputs
are HIGH when binary codes greater than nine are applied
TRUTH TABLE
A0
A1
A2
A3
0
1
2
3
4
5
6
7
8
9
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
L
H
H
L
L
H
H
L
L
H
H
L
L
H
H
L
L
L
L
H
H
H
H
L
L
L
L
H
H
H
H
L
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H = HIGH Voltage Level
L = LOW Voltage Level
GUARANTEED OPERATING RANGES
Min
Typ
Max
Unit
VCC
Symbol
Supply Voltage
Parameter
54
74
4.5
4.75
5.0
5.0
5.5
5.25
V
TA
Operating Ambient Temperature Range
54
74
– 55
0
25
25
125
70
°C
IOH
Output Current — High
54, 74
– 0.4
mA
IOL
Output Current — Low
54
74
4.0
8.0
mA
FAST AND LS TTL DATA
5-54
SN54/74LS42
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)
Limits
Symbol
Min
Parameter
VIH
Input HIGH Voltage
VIL
Input LOW Voltage
VIK
Input Clamp Diode Voltage
VOH
Output HIGH Voltage
VOL
Output LOW Voltage
IIH
Input HIGH Current
IIL
Input LOW Current
IOS
Short Circuit Current (Note 1)
ICC
Power Supply Current
Typ
Max
2.0
54
0.7
74
0.8
– 0.65
– 1.5
Unit
Test Conditions
V
Guaranteed Input HIGH Voltage for
All Inputs
V
Guaranteed Input LOW Voltage for
All Inputs
V
VCC = MIN, IIN = – 18 mA
54
2.5
3.5
V
74
2.7
3.5
V
VCC = MIN, IOH = MAX, VIN = VIH
or VIL per Truth Table
54, 74
0.25
0.4
V
IOL = 4.0 mA
74
0.35
0.5
V
IOL = 8.0 mA
VCC = VCC MIN,
VIN = VIL or VIH
per Truth Table
20
µA
VCC = MAX, VIN = 2.7 V
0.1
mA
VCC = MAX, VIN = 7.0 V
– 0.4
mA
VCC = MAX, VIN = 0.4 V
–100
mA
VCC = MAX
13
mA
VCC = MAX
Typ
Max
Unit
– 20
Note 1: Not more than one output should be shorted at a time, nor for more than 1 second.
AC CHARACTERISTICS (TA = 25°C)
Limits
Symbol
Min
Parameter
Test Conditions
tPLH
tPHL
Propagation Delay
(2 Levels)
15
15
25
25
ns
Figure 2
tPLH
tPHL
Propagation Delay
(3 Levels)
20
20
30
30
ns
Figure 1
VCC = 5.0 V
CL = 15 pF
AC WAVEFORMS
VIN
VOUT
1.3 V
1.3 V
tPHL
tPLH
1.3 V
VIN
1.3 V
1.3 V
tPLH
tPHL
VOUT
1.3 V
Figure 1
1.3 V
1.3 V
Figure 2
FAST AND LS TTL DATA
5-55