Before we begin: This article was written expecting that the reader should have some knowledge about what does 1 and 0 in input means. 1 means that circuit is on while 0 means that the circuit is off. Furthermore I don’t own any of the images used, the tables were taken from Cambridge IGCSE™ and O level Computer Science, the gates pictures were taken from Logic.ly and the proper circuit pictures were taken from Logic Gate simulator by academo
What are Logic Gates?
Thousands of logic gates comprise electronic circuits in computers, solid-state drives, and controlling devices. Logic gates accept binary inputs and output binary outputs. A logic circuit is made up of several logic gates that are linked together to perform a certain purpose.
In this article we will be going through seven different types of Logic Gates used in computers.
NOT Gate
Represented using the symbol below:
NOT gates does exactly the opposite of what you input. NOT gate, by it’s name it’s clear what the gate’s function is. It denies the input you give it and inverts it. For example: if you input 1 the output will be 0, and vice versa. The NOT gate only takes one input and outputs one value.
When applied it would be something like this:
Input Value 1:
Input Value 0:
AND Gate:
Represented using the symbol below:
The AND gate gets its name from its behavior, which is similar to the binary “and” operator, with 0 representing “false” and 1 representing “true.” This gate is represented visually by a symbol with input and output terminals on both the left and right sides. The output of this gate should only show “true” when both input signals are “true.” The output signal signifies “false” in all other instances. The AND gate is a logical operator that returns a binary value of 1 when both inputs are 1.
When applied it is something like this:
Inputs 1 and 1
Inputs 1 and 0
Inputs 0 and 0
OR Gate:
Represented using the symbol below:
The OR gate derives its name from the fact that it functions similarly to the logical inclusive “or.” The outcome is “true” if any of the inputs is “true.” If both inputs are “false,” the result will be “false.” In other words, for the output to be 1, one or both of the inputs must be 1.
When applied it is something like this:
Inputs 1 and 1
Inputs 1 and 0
Inputs 0 and 0
NAND Gate:
Represented by the symbol below:
The NAND gate (NOT with) combines a with gate with a NOT gate. It works in the same way as the logical operation “and” followed by negation. If both of the inputs are “true,” the result is “false.” Otherwise, the output is “true.”
When applied, it’s something like this:
Input 1 and 1:
Input 0 and 1:
Input 0 and 0:
NOR Gate:
Represented by the symbol below:
The NOR gate is a combination OR gate followed by an inverter. Its output is “true” if both inputs are “false.” Otherwise, the output is “false.”
When implemented, it is something like this:
Input 1 and 1:
Input 0 and 1:
Input 0 and 0:
XOR Gate:
Combining an XOR gate with an inverter yields the XNOR (exclusive-NOR) gate. If the inputs are same, the output is “true,” otherwise “false.”
When applied it is something like this:
Input 1 and 1:
Input 1 and 0:
Input 0 and 0:
