Digital Logic Fundamentals Unit 3 – Exclusive-OR/NOR Gates
The output (C) of an XNOR gate is logic 1 (high) when the gate inputs (A and B) are equal (both
high or both low).
An XNOR gate has a circle on the output in addition to the double curved lines at the input.
The Boolean equation for an XNOR gate is C = AB + AB, or simplified as C = A ⊕ B.
Above is the truth table for the XOR and XNOR functions. The XOR circuit detects conditions
of inequality at its input. The XNOR circuit detects conditions of equality at its input.