SN54AS181B, SN74AS181A

ARITHMETIC LOGIC UNITS/FUNCTION GENERATORS

SDAS209B – DECEMBER 1982 – REVISED DECEMBER 1994

5

POST OFFICE BOX 655303

signal designations

In Figures 1 and 2, the polarity indicators (

) indicate that the associated input or output is active low with

respect to the function shown inside the symbol. The symbols are the same in both figures. The signal

designations in Figure 1 agree with the indicated internal functions based on active-low data and are for use

with the logic functions and arithmetic operations shown in Table 1. The signal designations have been changed

in Figure 2 to accommodate the logic functions and arithmetic operations for the active-high data given in

Table 2. The SN54AS181B and SN74AS181A together with the

′S182 can be used with the signal designation

of either Figure 1 or Figure 2.

M

0

31

0

6

S0

5

S1

4

S2

3

S3

4

8

M

15

A = B

14

C1

7

17

16

9

10

11

13

P

2

Q

1

P

23

Q

22

P

21

Q

20

P

19

Q

18

ALU

[1]

[2]

[3]

[8]

Cn

A0

A1

A2

A3

B0

B1

B2

B3

(0 . . . 15) CP

(0 . . . 15) CG

6(P=Q)

(0 . . . 15) CO

P

G

Cn + 4

F0

F1

F2

F3

SN54AS181B,

SN74AS181A

M

0

31

0

6

S0

5

S1

4

S2

3

S3

4

8

M

15

A = B

14

7

17

16

F0

9

F1

10

F2

11

F3

13

P

2

Q

1

P

23

Q

22

P

21

Q

20

P

19

Q

18

ALU

[1]

[2]

[3]

[8]

Cn

A0

A1

A2

A3

B0

B1

B2

B3

(0 . . . 15) CP

(0 . . . 15) CG

6(P=Q)

(0 . . . 15) CO

X

Y

Cn + 4

SN54AS181B,

SN74AS181A

CP0

3

CG0

2

CPG

CP1

5

CG1

4

CP2

8

CG2

7

CP3

10

CG3

9

CP4

14

CG4

13

CP5

16

CG5

15

CP6

19

CG6

18

CP7

21

CG7

20

1

6

CO1

11

CO3

17

CO5

22

CO7

Cn

P0

G0

P1

G1

P2

G2

P3

G3

P4

G4

P5

G5

P6

G6

P7

G7

′S182

Cn + 8

Cn + 16

Cn + 24

Cn + 32

C1

CP0

3

CG0

2

CPG

CP1

5

X1

CG1

4

Y1

CP2

8

X2

CG2

7

Y2

CP3

10

X3

CG3

9

Y3

CP4

14

X4

CG4

13

Y4

CP5

16

X5

CG5

15

Y5

CP6

19

X6

CG6

18

Y6

CP7

21

X7

CG7

20

Y7

1

6

CO1

11

CO3

17

CO5

22

CO7

Cn

X0

Y0

′S182

Cn + 8

Cn + 16

Cn + 24

Cn + 32

Figure 1

Figure 2

(use with Table 1)

(use with Table 2)