54act283 National Semiconductor Corporation, 54act283 Datasheet - Page 2

• Manufacturer Part Number: 54act283
• Description: 4-bit Binary Full Adder With Fast Carry
• Manufacturer: National Semiconductor Corporation

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Functional Description
Note that as long as A
or LOW, they do not influence S
are the same the carry into the third stage does not influence
the carry out of the third stage. Figure 4 shows a method of
implementing a 5-input encoder, where the inputs are
FIGURE 3. 2-Bit and 1-Bit Adders
Active HIGH: 0 + 10 + 9 = 3 + 16
Logic Levels
Active HIGH
Active LOW
FIGURE 2. 3-Bit Adder
2
and B
2
C
are the same, whether HIGH
L
0
1
2
0
. Similarly, when A
FIGURE 1. Active HIGH versus Active LOW Interpretation
A
L
0
1
0
(Continued)
Active LOW: 1 + 5 + 6 = 12 + 0
A
H
1
0
1
DS100977-5
A
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L
0
1
2
2
and B
A
H
1
0
3
2
B
H
1
0
2
0
equally weighted. The outputs S
nary number equal to the number of inputs I
true. Figure 5 shows one method of implementing a 5-input
majority gate. When three or more of the inputs I
true, the output M
B
L
0
1
1
B
L
0
1
2
FIGURE 5. 5-Input Majority Gate
B
H
1
0
3
FIGURE 4. 5-Input Encoder
5
S
H
1
0
is true.
0
S
H
1
0
1
S
L
0
1
2
0
, S
1
S
L
0
1
and S
3
C
H
1
0
2
DS100977-7
4
present a bi-
1
DS100977-8
–I
5
1
that are
–I
5
are