MM74C90 Fairchild, MM74C90 Datasheet - Page 2

• Manufacturer Part Number: MM74C90
• Description: 4-Bit Decade Counter 4-Bit Binary Counter
• Manufacturer: Fairchild

www.fairchildsemi.com
Logic Diagrams
Truth Tables
Output Q
H
L
X
MM74C90 4-Bit Decade Counter BCD Count Sequence
LOW Level
HIGH Level
Irrelevant
A
is connected to Input B for BCD count.
Count
0
1
2
3
4
5
6
7
8
9
Q
H
H
MM74C90
L
L
L
L
L
L
L
L
D
Q
H
H
H
H
L
L
L
L
L
L
Output
C
Q
H
H
H
H
L
L
L
L
L
L
B
Q
H
H
H
H
H
L
L
L
L
L
A
2
MM74C93 4-Bit Binary Counter Binary Count Sequence
Output Q
H
L
X
LOW Level
HIGH Level
Irrelevant
A
is connected to input B for binary count sequence.
Count
10
11
12
13
14
15
0
1
2
3
4
5
6
7
8
9
Q
H
H
H
H
H
H
H
H
MM74C93
L
L
L
L
L
L
L
L
D
Q
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
Output
C
Q
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
B
Q
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
A