✏️ Explanatory Question
[Computer Hardware]
Question:
Write the canonical Product-of-Sum (POS) expression for the Sum and Carry of a Full Adder.
[Computer Hardware]
Question:
Write the canonical Product-of-Sum (POS) expression for the Sum and Carry of a Full Adder.
Answer:
Sum (S):
S(A,B,C) = ΠM(0,3,5,6)
Carry (C):
C(A,B,C) = ΠM(0,1,2,4)
Explanation:
A Full Adder has three inputs:
A, B, C (Carry input)
and two outputs:
Truth Table of Full Adder:
A B C | S CARRY
0 0 0 | 0 0
0 0 1 | 1 0
0 1 0 | 1 0
0 1 1 | 0 1
1 0 0 | 1 0
1 0 1 | 0 1
1 1 0 | 0 1
1 1 1 | 1 1
Canonical POS Form:
In Product-of-Sums (POS), we take the rows where output is 0.
For Sum (S):
Output S = 0 for rows:
0, 3, 5, 6
Therefore:
S(A,B,C) = ΠM(0,3,5,6)
For Carry (C):
Output Carry = 0 for rows:
0,1,2,4
Therefore:
C(A,B,C) = ΠM(0,1,2,4)
Conclusion:
ΠM(0,3,5,6)
ΠM(0,1,2,4)