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IC BLOCK DIAGRAMS AND TERMINAL DESCRIPTIONS -71
Q7172: TC74VHC138FT (3-8 Line Decoder)
BLOCK DIAGRAM
DTC-9.8
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
A
B
C
G2A
G2B
G1
Y7
GND
V
CC
Y0
Y1
Y2
Y3
Y4
Y5
Y6
ENABLE INPUTS
SELECT INPUTS
OUTPUTS
G1
G2A
G2B
C
B
A
Y0
Y1
Y2
Y3
Y4
Y5
Y6
Y7
X
H
X
X
X
X
H
H
H
H
H
H
H
H
X
X
H
X
X
X
H
H
H
H
H
H
H
H
L
X
X
X
X
X
H
H
H
H
H
H
H
H
H
L
L
L
L
L
L
H
H
H
H
H
H
H
L
L
L
H
H
L
H
H
H
H
H
H
L
L
H
L
H
H
L
H
H
H
H
H
L
L
H
H
H
H
H
L
H
H
H
H
L
H
L
L
H
H
H
H
L
H
H
H
L
H
L
H
H
H
H
H
H
L
H
H
L
H
H
L
H
H
H
H
H
H
L
H
L
H
H
H
H
H
H
H
H
H
H
L
Logic Diagram
G1
G2B
G2A
C
B
A
Y7
Y6
Y5
Y4
Y3
Y2
Y1
Y0
Data
Outputs
Select
Inputs
Enable
Inputs
1
2
3
4
5
6
15
14
13
12
11
10
9
7
www. xiaoyu163. com
QQ 376315150
9
9
2
8
9
4
2
9
8
TEL 13942296513
9
9
2
8
9
4
2
9
8
0
5
1
5
1
3
6
7
3
Q
Q
TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299