34 lines
1.4 KiB
Markdown
34 lines
1.4 KiB
Markdown
---
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tags:
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- Logic
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- Electronics
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- Hardware
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- logic-gates
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---
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# NOT gate
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This gate corresponds to the `NOT` Boolean or negation logical connective. It is really simple and derived from the trivial logical fact that `true` is `true` and `false` is `false` also known as **logical identity**.
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### Natural language
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>
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> The negation operator (`¬` or `~` ) switches the value of a proposition from `true` to `false`. When we put `~` before `true` it becomes `false` and when we put `~` before `false` it becomes `true` .
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### Truth table
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This corresponds to a simple on-off switch.
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In terms of logic gates we would create this by using a single NAND gate. Although it can take a total of two inputs, it would be controlled by a single switch, so both inputs would be set to `1 1` or `0 0` when the switch is activated and deactivated. This would remove the `AND` aspect of `NAND` and reduce it to `NOT` .
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A NAND gate simulating NOT logic
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TO DO: Come back to this with new book and explain better how a NAND can be reduced to NOT.
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### Symbol for `NOT` gate
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NOT has its own electrical symbol to distinguish it from a NAND:
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