HD74LS42
Function Table
No.
0
1
2
3
4
5
6
7
8
9
BCD input
D
L
L
L
L
L
L
L
L
H
H
H
H
H
H
H
C
L
L
L
L
H
H
H
H
L
L
L
L
H
H
H
B
L
L
H
H
L
L
H
H
L
L
H
H
L
L
H
H
A
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
0
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
1
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
2
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
H
3
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
Decimal output
4
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
5
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
6
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
7
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
H
8
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
H
9
H
H
H
H
H
H
H
H
H
L
H
H
H
H
H
H
Invalid
H
H
H; high level, L; low level
Block Diagram
A
A
A
0Y
1Y
2Y
B
Inputs
B
C
C
C
D
D
4Y
Outputs
5Y
6Y
7Y
8Y
9Y
B
3Y
D
Absolute Maximum Ratings
Item
Supply voltage
Input voltage
Power dissipation
Storage temperature
Symbol
V
CC
V
IN
P
T
Tstg
Ratings
7
7
400
–65 to +150
Unit
V
V
mW
°C
Note: Voltage value, unless otherwise noted, are with respect to network ground terminal.
Rev.3.00, Jul.22.2005, page 2 of 6