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Ara Melkonyan
Ara Melkonyan

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LOGIC GATES AND THEIR USAGE

Everything in the world of electronics comes down to binary operations. These are operations with one or more inputs that always produce a single binary output. Without these building blocks, no technological revolution of computers, phones, and operating systems would happen. In this short blog, we’ll explore the world of logic gates, their types, and how they are used in modern technology.

So, what are Logic Gates?
Logic gates are basic building blocks for digital circuits that perform Boolean operations with one or more binary inputs. The inputs are usually 0s and 1s. They represent off and on, false and true. Each logic gate does a specific Boolean function, such as NOT, AND, OR, etc. These gates are usually combined to create digital circuits and perform more complex calculations.

Types of Logic Gates
The simplest logic gates are the Buffer and the Inverter (the NOT logic gate). The buffer is just a logic gate that copies the input. The inverter, on the other hand, does the opposite, it inverts the input. When given one, it outputs zero, and, when given zero, it outputs one.
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The AND logic gate is very useful when every condition must be met for the result to be positive. It outputs 1 if all inputs are 1.

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The OR logic gate outputs 1 when any of its inputs are 1. The OR gate usually helps when at least one condition must be true to trigger an event.

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The NAND and NOR logic gates are the opposites of AND and OR respectively. NAND outputs 1 until all inputs are 1. It's very widely used because of its versatility: every other gate can be built using NAND gates alone.
And NOR outputs 1 when all inputs are 0.

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The X in XOR and XNOR means "exclusive". XOR outputs 1 when one of the inputs is 1, but not both. It's very common in systems where we need to find the difference or sum of two inputs. XNOR outputs 1 when both inputs are the same and is often used in error checking and parity operations.

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Examples of Logic Gate usage
In CPU-s millions and, sometimes, billions of transistors are organized into logic gates. These gates are formed into circuits that perform arithmetic and logical operations, decision-making operations and store data. In devices like RAM or ROM, logic gates are used to store and retrieve data in binary form. Even the braking system of your car uses logic gates to ensure that they behave predictably in different situations.

Conclusion
Logic gates might seem very simple, but the build the foundations of the biggest of systems. Whenever you play video games, work on your laptop or just surf the internet, logic gates are working hard, processing information and making decision in the blink of an eye. Understanding how logic gates work and where they are used is crucial to enter into the world of computer science and engineering.

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