Description
A Logic XNOR (Exclusive NOR) gate is a digital logic gate that produces a true output (1) only when all of its inputs are the same (either all are true or all are false). It performs a logical equality operation, acting as the inverse of an XOR gate, and can be built from basic AND, OR, and NOT gates. XNOR gates are useful for comparing binary values and detecting phase differences in digital systems
Features
- Logical Equality: The XNOR gate's output is true (1) if all of its inputs are identical and false (0) if any input differs.
- Truth Table: For two inputs (A and B), the truth table shows:
A=0, B=0 → Output=1
A=0, B=1 → Output=0
A=1, B=0 → Output=0
A=1, B=1 → Output=1
- Boolean Expression: The output (Y) of a two-input XNOR gate can be represented as:
Y = A ⊙ B (A circled dot B)
Y = AB + ĀB̄ (where 'AB' is A AND B, 'Ā' is NOT A, 'B̄' is NOT B)
- Symbolic Representation
The symbol for an XNOR gate is an XOR gate symbol with a small "bubble" (a small circle) at the output, indicating inversion.