What is the function of a NOT gate in digital logic?

What is the function of a NOT gate in digital logic?

• A. Passes the input unchanged
• B. Inverts the input
• C. Applies a delay to the input
• D. Converts the input to a different voltage level

Answer: (B)

A NOT gate provides inversion: its output is the opposite of its input. If the input is a high (1), the output is low (0); if the input is low (0), the output is high (1). This simple inversion is the foundation for building complex logic, allowing you to negate signals and combine with other gates to realize any boolean function. It’s not simply passing the input unchanged—that would be a buffer. It also doesn’t primarily change the voltage level like a level shifter; while real gates have some propagation delay, the defining behavior is the logical negation.

A NOT gate provides inversion: its output is the opposite of its input. If the input is a high (1), the output is low (0); if the input is low (0), the output is high (1). This simple inversion is the foundation for building complex logic, allowing you to negate signals and combine with other gates to realize any boolean function. It’s not simply passing the input unchanged—that would be a buffer. It also doesn’t primarily change the voltage level like a level shifter; while real gates have some propagation delay, the defining behavior is the logical negation.