An XNOR gate, also known as an “equivalence gate,” is a logic gate with two or more inputs and one output. The output of an XNOR gate is high (1) when all of its inputs are the same, either all 1’s or all 0’s. Otherwise, the output is low (0). In other words, an XNOR gate behaves like an OR gate, followed by a NOT gate.
The symbol for an XNOR gate is a rectangle with a curved line on the left and right sides, two or more inputs extending from the top, and a single output extending from the bottom.
XNOR Gate Truth Table
XNOR Gate Equivalence Circuit
Applications of XNOR gate:
- Digital arithmetic: XNOR gates can be used in digital arithmetic circuits, such as binary adders and subtractors. For example, two binary numbers can be added using XNOR gates by first adding the bits using XOR gates and then using an XNOR gate to determine the carry bit.
- Code converters: XNOR gates can be used in code converters, which convert a binary code into another code, such as BCD (binary-coded decimal) or Gray code.
- Comparator circuits: XNOR gates can be used in comparator circuits to compare two binary numbers and determine whether they are equal or not.
- Parity generators/checkers: XNOR gates can be used in parity generators and checkers to detect errors in digital data transmission.
- Boolean logic circuits: XNOR gates can be used in various Boolean logic circuits, such as multiplexers, demultiplexers, and flip-flops.