# Clarity on XNOR Gate

The Exclusive-NOR or XNOR gate is a digital logic gate that takes more than 2 inputs but only outputs one and the Boolean equation is Y is equal to A.B+A'B' when there is input A and input B.

By integrating the XOR gates as well as NOT gates, the Exclusive-NOR gate is created. According to truth table of XNOR gate, the outputs are comparable to that of a regular NOR gates, excluding that the XNOR gate’s output stays higher when both inputs are higher. When both inputs are1 (high), the output of the XNOR gate is 1; if both inputs are 0, then output is 0 (low). Then output is 0 (low) when either input is 1 that is high. In other words, for the output to be 1, both inputs must be at the similar logic levels.

## The Boolean Expression and the Symbol

An XNOR gate’s logic symbol is an Exclusive-OR gate along with “inversion bubbles” or circle in the front. As a result, the XNOR gate is a variant of the XOR gate. The XNOR gate’s Boolean expression is as follows:

A Truth Table of XNOR Gates

 A B Y 1 1 1 0 1 0 0 0 1 1 0 0

The outputs of a three-input XNOR gates can be determined using the same logic. The following is the Boolean equation for it-

## A Truth Table of the 3-input XNOR Gates

 A B C Y 0 0 0 1 0 1 1 1 0 0 1 0 0 1 0 0 1 1 1 0 1 0 1 1 1 0 0 0 1 1 0 1

Using gates like AND, OR, and NOT, we may create the XNOR or Ex-NOR gate. The biggest drawback of this approach is that we combine several types of gates to create a single Ex-NOR gate. We can also construct the XNOR gates using only NAND gates. This is a more straightforward method of achieving Ex-NOR gates functionality.

## Applications of the XNOR Gates

XNOR gates are mostly employed in the electronic circuits that conduct data checking and arithmetic operations, such as Subtractions, adders, and Parity Checkers, among other things. X-NOR gates are employed in Digital Comparator circuits because they produce a logic level “1” output when their two inputs are equal. This allows them to evaluate the magnitude of the 2 binary numbers or digits.

## The Construction

The water is heated using the circuit. There are 2 float indicators and two outlets on this device. Then a float indicator is attached to the XNOR gate’s inputs. The alarm circuit is associated to the XNOR gate’s output, which is used to notify when the level of the water in a glass beaker changes. A heating system element is located at the bottommost part of a beaker and is used to heat a specific volume of water.

Subsequently, when water level rises to a certain point, the higher outlet will overflow. As soon as the water level falls below a certain level, then the heating element at the bottommost part is exposed and will then burn out. Subsequently, it sends out an alert when level of the water rises or falls to a specific level. The float switch must be set at the high and low levels of water within the tank to accomplish this.

The float indicator is pushed up when it comes into touch with the water level. The float’s leaver will be disconnected from the armature as a result of this. The XNOR gate input is 0 in this case. When the float indicator is not in connection with the level of the water, a lever is linked to the +5 Volts supply, which activates the armature. The XNOR gate’s inputs will be higher in this case, which is equivalent to one. When the two leavers are linked to +5 V source or to the voltage of the ground, the XNOR gate’s two inputs are 1, and the XNOR gate’s output is high, activating the alarms and alerting the individual.

When the level of water is between the upper and the low floater indicators, logic 1 from the up indicator and the logic zero from the lower indicator are applied to the XNOR gate’s input. Because the level of water is at the required level, no alert will sound. The logic Ex-NOR gates are employed as heat exchanger circuits in this example.

## Conclusion

The XNOR gates is a logic gate which is digital that takes more than 2 inputs however merely outputs one. The XNOR Gate’s output is ‘High’ if both of the inputs are higher. The outputs are lower when both of the inputs are lower. The outputs is ‘Low’ if one of the inputs is ‘Low.’ and the Boolean equation is Y is equal to A.B+A’B’ if there is inputs A and input B.