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Logic gates
Intermediate
AND, OR, NOT built from transistors.
AND, OR, NOT, NAND, NOR, XOR built from transistors process binary signals. Combinations make adders, memory and computers.
AND outputs 1 only if both inputs are 1.
NAND is universal.
In more detail
Logic gates perform basic Boolean operations such as AND, OR, NOT and NAND on electrical signals. They are built from transistors and form the basis of digital circuits.
Real-world uses
- Computers perform calculations using combinations of logic gates.
- Alarm systems combine sensor inputs using logic gates.
- Computer processors are built from billions of logic gates that combine signals to perform calculations.
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Frequently asked questions
What is a NAND gate?
An AND gate followed by a NOT, which is universal and can build any other gate.
What does a truth table show?
All possible input combinations and their outputs.
What does an AND gate do?
It gives a high output only when both of its inputs are high.
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