Medium
EST. TIME: 45 minHalf Adder and Full Adder
To design and verify the truth table of Half Adder and Full Adder using 74xx family ICs.
Theory
Adders are combinational circuits used for binary addition.
Half Adder
Adds two single binary digits. Has two outputs: Sum (S) and Carry (C).
S = A ⊕ B, C = A • B
Full Adder
Adds three binary digits (A, B, Cin). Has two outputs: Sum (S) and Carry (Cout).
S = A ⊕ B ⊕ Cin, Cout = (A • B) + (Cin • (A ⊕ B))
Procedure
- Half Adder: Connect one XOR gate and one AND gate as per the circuit diagram. Verify inputs and outputs.
- Full Adder: Use two Half Adders and an OR gate, or implement using basic gates.
- Apply all combinations of inputs and check the Sum and Carry LEDs.