SN74AS882A Datasheet, PDF (1/9 Pages) Texas Instruments – 32-BIT LOOK-AHEAD CARRY GENERATORS

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SN54AS882A, SN74AS882A
32ĆBIT LOOKĆAHEAD CARRY GENERATORS
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SDAS235 − D2661, DECEMBER 1982 − REVISED NOVEMBER 1985
• Directly Compatible With ’AS181B,
’AS1181, ’AS881B, and ’AS1881 ALUs
• Package Options Include Plastic Small
Outline Packages, Both Plastic and
Ceramic Chip Carriers, and Standard
Plastic and Ceramic 300-mil DIPs
• Capable of Anticipating the Carry Across a
Group of Eight 4-Bit Binary Adders
• Cascadable to Perform Look-Ahead Across
n-Bit Adders
• Typical Carry Time, C_n to Any C_n+i, is Less
Than 6 ns
• Dependable Texas Instruments Quality and
Reliability
SN54AS882A . . . JT PACKAGE
SN74AS882A . . . DW OR NT PACKAGE
(TOP VIEW)
C_{n 1}
G0 ₂
P0 ₃
G1 ₄
P1 ₅
C_{n + 8 6}
G2 7
P2 8
G3 9
P3 10
C_{n − 16} 11
GND 12
24 ^V_CC
23 ^NC
22 ^C_{n + 32}
21 ^P7
20 ^G7
19 ^P6
18 G6
17 C_{n + 24}
16 P5
15 G5
14 P4
13 G4
description
The ’AS882A is a high-speed look-ahead carry
generator capable of anticipating the carry across
a group of eight 4-bit adders permitting the
designer to implement look-ahead for a 32-bit ALU
with a single package or, by cascading ’AS882As,
full look-ahead is possible across n-bit adders.
The SN54AS882A is characterized for operation
over the full military temperature range of − 55°C
to 125°C. The SN74AS882A is characterized for
operation from 0°C to 70°C.
’AS882A LOGIC EQUATIONS
C_n+8 = G1 + P1G0+P1P0C_n
C_n+16 = G3 + P3G2 + P3P2G1 + P3P2P1G0
+ P3P2P1P0C_n
SN54AS882A . . . FK PACKAGE
SN74AS882A . . . DW OR NT PACKAGE
(TOP VIEW)
G1
P1
C_{n + 8}
NC
G2
P2
G3
4 3 2 1 28 27 26
5
25
6
24
7
23
8
22
9
21
10
20
11
19
12 13 14 15 16 17 18
P7
G7
P6
NC
G6
C_{n + 24}
P5
C_n+24 = G5 + P5G4 + P5P4G3 + P5P4P3G2
+ P5P4P3P2G1 + P5P4P3P2P1G0
+ P5P4P3P2P1P0C_n
C_n+32 = G7 + P7G6 + P7P6G5 + P7P6P5G4
+ P7P6P5P4G3 + P7P6P5P4P3G2
+ P7P6P5P4P3P2G1 + P7P6P5P4P3P2P1G0
+ P7P6P5P4P3P2P1P0C_n
NC − No internal connection
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
• POST OFFICE BOX 1443 HOUSTON, TEXAS 77001
Copyright  1985, Texas Instruments Incorporated
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