NAND gate facts for kids

A NAND gate is a special electronic switch that helps computers and other digital devices make decisions. Think of it like a tiny brain for circuits! It takes two inputs, usually called A and B, and gives one output.

Here's how it works:

• If input A is "off" (false) and input B is "off" (false), the NAND gate's output is "on" (true).
• If input A is "off" (false) and input B is "on" (true), the output is still "on" (true).
• If input A is "on" (true) and input B is "off" (false), the output is also "on" (true).
• But, if both input A and input B are "on" (true), then the NAND gate's output turns "off" (false).

So, the NAND gate's output is only "off" when both inputs are "on." Otherwise, it's always "on." This makes the NAND gate very useful. It's even called a "universal gate" because you can build any other type of logic gate using only NAND gates!

How NAND Gates Look

Engineers and scientists use special symbols to draw NAND gates in circuit diagrams. There are a few different ways to show them, depending on where you are in the world or what standard is being used. These symbols help everyone understand how the circuits are put together.

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  This is the common 'distinctive shape' NAND symbol, often used in the US.

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  This is the 'military' NAND symbol, used in some places like Germany.

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  This is the 'rectangular' NAND symbol, used by an international standard group called IEC.

Images for kids

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  This is a real computer chip called the TTL 7400. It contains four separate NAND gates inside! The extra pins are for power and ground connections.

See also

In Spanish: Puerta NAND para niños