© 2000 Fairchild Semiconductor Corporation DS006378 www.fairchildsemi.com
August 1986
Revised March 2000
DM74LS83A 4-Bi
t Bina
ry Adder w
i
th

Fast

Car
r
y
DM74LS83A
4-Bit Binary Adder with Fast Carry
General Description
These full adders perform the addition of two 4-bit binary
numbers. The sum (∑) outputs are provided for each bit
and the resultant carry (C4) is obtained from the fourth bit.
These adders feature full internal look ahead across all four
bits. This provides the system designer with partial look-
ahead performance at the economy and reduced package
count of a ripple-carry implementation.
The adder logic, including the carry, is implemented in its
true form meaning that the end-around carry can be
accomplished without the need for logic or level inversion.
Features
a73 Full-carry look-ahead across the four bits
a73 Systems achieve partial look-ahead performance with
the economy of ripple carry
a73 Typical add times
Two 8-bit words 25 ns
Two 16-bit words 45 ns
a73 Typical power dissipation per 4-bit adder 95 mW

Ordering Code:
Connection Diagram
Order Number Package Number Package Description
DM74LS83AN N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide