Week 4 - Digital Logic Circuits (Logic Gates)

A logic gate is a basic building block of digital systems, found in most digital devices. It performs functions consistent with Boolean operators, either allowing or stopping electrical signals based on logical conditions, and is typically built using transistors.

To understand how a computer works and operates at the hardware level.

Combinational Logic depends only on present inputs, while Sequential Logic depends on both current inputs and previous outputs (has memory).

Basic Gates (AND, OR, NOT), Universal Gates (NAND, NOR), Exceptional Gates (EX-OR, EX-NOR)

A NOT gate has one input and inverts it — 0 becomes 1, and 1 becomes 0. Boolean: Q = A'

An AND gate outputs 1 only if all inputs are 1. Boolean: Q = A ⋅ B

A NAND gate outputs 1 unless all inputs are 1. It is the inverse of AND. Boolean: Q = (A ⋅ B)'

An OR gate outputs 1 if at least one input is 1. Boolean: Q = A + B

A NOR gate outputs 1 only if all inputs are 0. It is the inverse of OR. Boolean: Q = (A + B)'

An EX-OR gate outputs 1 if inputs are different (one is 0, one is 1). Boolean: Q = A ⊕ B

An EX-NOR gate outputs 1 if inputs are the same (both 0 or both 1). Boolean: Q = A ⊙ B