1. Basic Logic Gates (Two Variables) 1.1. AND Gate Symbol: A B Y Equation: $Y = A \cdot B$ (or $Y = AB$) Truth Table: A B Y 0 0 0 0 1 0 1 0 0 1 1 1 1.2. OR Gate Symbol: A B Y Equation: $Y = A + B$ Truth Table: A B Y 0 0 0 0 1 1 1 0 1 1 1 1 1.3. NOT Gate (Inverter) Symbol: A Y Equation: $Y = \bar{A}$ (or $Y = A'$) Truth Table: A Y 0 1 1 0 1.4. NAND Gate Symbol: A B Y Equation: $Y = \overline{A \cdot B}$ Truth Table: A B Y 0 0 1 0 1 1 1 0 1 1 1 0 1.5. NOR Gate Symbol: A B Y Equation: $Y = \overline{A + B}$ Truth Table: A B Y 0 0 1 0 1 0 1 0 0 1 1 0 1.6. XOR Gate (Exclusive OR) Symbol: A B Y Equation: $Y = A \oplus B = A\bar{B} + \bar{A}B$ Truth Table: A B Y 0 0 0 0 1 1 1 0 1 1 1 0 1.7. XNOR Gate (Exclusive NOR) Symbol: A B Y Equation: $Y = \overline{A \oplus B} = AB + \bar{A}\bar{B}$ Truth Table: A B Y 0 0 1 0 1 0 1 0 0 1 1 1 2. Logic Gates (Three Variables: A, B, C) 2.1. AND Gate (3-input) Symbol: A B C Y Equation: $Y = A \cdot B \cdot C$ Truth Table: A B C Y 0 0 0 0 0 0 1 0 0 1 0 0 0 1 1 0 1 0 0 0 1 0 1 0 1 1 0 0 1 1 1 1 2.2. OR Gate (3-input) Symbol: A B C Y Equation: $Y = A + B + C$ Truth Table: A B C Y 0 0 0 0 0 0 1 1 0 1 0 1 0 1 1 1 1 0 0 1 1 0 1 1 1 1 0 1 1 1 1 1 2.3. NAND Gate (3-input) Symbol: A B C Y Equation: $Y = \overline{A \cdot B \cdot C}$ Truth Table: A B C Y 0 0 0 1 0 0 1 1 0 1 0 1 0 1 1 1 1 0 0 1 1 0 1 1 1 1 0 1 1 1 1 0 2.4. NOR Gate (3-input) Symbol: A B C Y Equation: $Y = \overline{A + B + C}$ Truth Table: A B C Y 0 0 0 1 0 0 1 0 0 1 0 0 0 1 1 0 1 0 0 0 1 0 1 0 1 1 0 0 1 1 1 0
