TLF9821

June 1992

DM54LS181DM74LS181

4-Bit Arithmetic Logic Unit

General Description

The ’LS181 is a 4-bit Arithmetic Logic Unit (ALU) which can

perform all the possible 16 logic operations on two variables

and a variety of arithmetic operations

Features

Y

Provides 16 arithmetic operations add subtract com-

pare double plus twelve other arithmetic operations

Y

Provides all 16 logic operations of two variables exclu-

sive-OR compare AND NAND OR NOR plus ten

other logic operations

Y

Full lookahead for high speed arithmetic operation on

long words

Connection Diagram

Dual-In-Line Package

TLF9821 – 1

Order Number DM54LS181J DM54LS181W or DM74LS181N

See NS Package Number J24A N24A or W24C

Pin Names

Description

A0–A3

Operand Inputs (Active LOW)

B0–B3

Operand Inputs (Active LOW)

S0 – S3

Function Select Inputs

M

Mode Control Input

Carry Input

F0–F3

Function Outputs (Active LOW)

Comparator Output

G

Carry Generate Output (Active LOW)

P

Carry Propagate Output (Active LOW)

Carry Output

C1995 National Semiconductor Corporation

RRD-B30M115Printed in U S A