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Hello everyone, in this lesson we will learn about AND gates in gate circuits

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AND gate is the most widely used gate circuit in PC

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Its circuit symbol is shown in Fig.

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We can know from the circuit diagram symbols that the AND gate has two input terminals and one output terminal

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What is the connection between its input and output? You can observe the following picture

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This is a very simple circuit

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It has two switches A and B

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When the A switch is closed and the B switch is not closed, the circuit cannot be conducted,

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and the small light bulb will not light up.

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Only when the two switches A and B are closed at the same time,

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the circuit can be turned on and the small light bulb can be lit

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This is the operation logic of AND gate

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Its logic is that it will output a high level when both input levels of A and B are high.

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We can also record the operation logic of the AND gate as AND multiplication

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Multiplying can also be written as A times B equals C

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Multiplying the two inputs equals the output

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Because it is a digital circuit, A, B, and C all have only two values, either 0 or 1

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Suppose A is equal to 1 and B is equal to 0, then the result of 1*0 is 0

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So if C is 1, then both A and B must be 1.

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This is the operation logic of AND gate