Short Notes on AND Gate

AND gate is a logic gate  that works like a multiplication operation. Similar to multiplication, if all of the inputs are high then the corresponding result will be high in the AND gate and if a single output is low the corresponding result will also be low.

Here the low output is zero while yeh high is one. Coming to the use, integrated circuits and the most common gates generally have two or three input channels.

Principle or Working

As mentioned earlier that AND gate works by performing logical multiplication and to be more specific we can say it performs binary multiplication . As we know. That there are two binary digits zero (0) and one (1) and their multiplication in various permutations gives rise to various inputs that can be made into an AND gate and the respective outputs or results on multiplication as the output of the gate. 

The various outputs of any logic gate are represented in a tabular format that is called the Truth table .

Now let’s see the possible inputs and the corresponding outputs in the AND logic gate . considering a two input AND gate .

Case 1 

0 at the first gate and 0 at the second gate 

That further can be written in binary multiplication as -:

0× 0 = 0  hence the result is low

Case 2

0 at the first gate and 1 at the second gate 

That further can be written in binary multiplication as -:

0× 1 = 0  hence the result is low

Case 3

1 at the first gate and 0 at the second gate 

That further can be written in binary multiplication as -:

1× 0= 0  hence the result is low

Case 4

1at the first gate and 1 at the second gate 

That further can be written in binary multiplication as -:

1× 1 = 1  hence the result is high

So from the above results we can prove the statement that if any of the inputs in a logic gate is low then the corresponding result will be low and both inputs have to be high in order to get a high result.

Or we can say that an AND gate is a device that produces a High input when all the inputs are high and the low input in all the other cases.Here a high result means getting a result of 1 while the low result means getting a result as 0. Also the AND gate can vary to two or three input channels but the output will only be one

AND Gate Equation 

The equation representing the AND gate is similar to that of Multiplication . 

X= A.B

Here X is the output and A and B are the two inputs which are multiplied to get the output. The dot represents Multiplication.

Here A,B and X can be 0 or 1 .

Truth Table of Two Input AND Gate 

A truth table is a tabular representation of all the possible inputs and the resulting outputs post binary multiplication that are possible in an AND gate .

The truth table of a two input AND gate is as follows 

Three Input AND gate

In a three input AND gate- A,B,C are the input gates and x is the output gate.

The truth table for a three input AND gate is as follows

AND gate is generally designed for diodes or transistors.

Application of AND Gates 

AND gates are used in various fields Like in data transmission and control, in various alarm circuits and in digital measuring devices.

Conclusion 

AND gate is a logic gate used in various integrated circuits . It has two or three input channels and one output channel. The basic principle on which it works is binary multiplication. Binary digits are 0 and 1. So multiplication of these duguta in various permutations and combinations is the Truth table of the AND gate. The truth table has the possible inputs and resulting outputs which are represented in a tabular form . Being closely aligned to the principles of multiplication , the AND gate gives a high response only when all the inputs to the digital device are high . The corresponding equation that represents AND gate is  X= A.B.