Logic Gates

Logic gates are the basic building blocks of any digital system. Generally, a digital circuit will consists of number of logic gates, which receive the binary inputs and perform a logical operations like AND, OR and NOT.

There are two states in digital logic circuit design – Logic ‘0’ and Logic ‘1’ or FALSE and TRUE or LOW and HIGH value. These states can be explained with a simple lamp switch. The lamp has only two states in its operation – either be turned ON or turned OFF. The ON state represents the HIGH voltage and the OFF state represents the LOW voltage value.

In the same way, the state of the digital system is defined. Logic 1 represents HIGH or TRUE output and Logic 0 represents LOW or FALSE output.

These two states are commonly represented as 0 and 1 in number systems, boolean algebra and truth table of logic gates. The number system and boolean algebra can be implemented with these gates.

Different types of Logic Gates

The available gates are AND, OR, NOT, NOR, NAND, Ex-OR and Ex-NOR gate. Among which AND, OR, NOT gate are the basic gates, whereas NAND and NOR gate are the universal gates. Let us take a look at all the gates in detail below.

AND gate

OR gate

NOT gate

NAND gate

NOR gate

Ex-OR gate

Ex-NOR gate

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Comparison of Truth table of different logic gates

For your clear understanding, the below table is given, which shows the comparison between different gates.