Following Multiplexer circuit is equivalent to ISRO 2020
2020
Following Multiplexer circuit is equivalent to 
ISRO 2020
- A.
Sum equation of full adder
- B.
Carry equation of full adder
- C.
Borrow equation for full subtractor
- D.
Difference equation of a full subtractor
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Correct answer: A
The circuit consists of a 4-to-1 Multiplexer (MUX) with select lines A and B connected to S0 and S1 respectively.
The data inputs are configured as follows: Input 0 is connected to C, Input 1 and Input 2 are connected to the complement of C (NOT C), and Input 3 is connected to C.
The Boolean expression for the output Y is: Y = (B' A')C + (B' A)C' + (B A')C' + (B A)C.
This expression simplifies to Y = A XOR B XOR C, which is the standard Sum equation for a Full Adder.
Therefore, the circuit is equivalent to a Full Adder.
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