SN74AHCT138QQ1

3LINE TO 8LINE DECODER/DEMULTIPLEXER

SGDS022A − FEBRUARY 2002 − REVISED APRIL 2008

2

POST OFFICE BOX 655303

FUNCTION TABLE

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

XH

X

XX

H

HH

HH

HH

H

L

XX

X

XX

H

HH

HH

HH

H

H

LL

L

LL

L

HH

HH

HH

H

H

LL

L

LH

H

L

H

HH

HH

H

H

LL

L

HLH

H

L

HH

HH

H

H

LL

L

HH

H

HH

L

H

HH

H

H

LL

H

LL

H

HH

H

L

HH

H

H

LL

H

LH

H

HH

HH

L

H

H

H

LL

H

HLH

HH

HH

H

L

H

H

L

L

H

H

H

H

H

H

H

H

H

H

L

BIN/OCT

1

1

A

2

2

B

4

3

C

4

5

6

G1

Y0

15

0

&

EN

Y1

14

1

Y2

13

2

Y3

12

3

Y4

11

4

Y5

10

5

Y6

9

6

Y7

7

7

DMUX

0

1

A

2

B

2

3

C

4

5

6

G1

Y0

15

0

&

Y1

14

1

Y2

13

2

Y3

12

3

Y4

11

4

Y5

10

5

Y6

9

6

Y7

7

7

G

7

0

G2A

G2B

G2A

G2B

† These symbols are in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.