DIGITAL LOGIC GATES

Introduction

1.     Basic Logic Gates

2.     Truth Tables

3.     Logical Functions

·         Truth Tables

·         Logical Expression

·         Graphical Form

Most Difficult Reading Topics

• Logic gates and figuring out how to readthem

• Logical Circuit Equivalence

• NAND NOR and XOR truth tables

• Using the rules to create and read thelogic gates using 0's and 1's

• Transistor implementation

• Difference between positive logic and negative logic

Logic

• Formal logic is a branch of mathematics that deals with true and false values instead of numbers.

• In the mid-19th century, George Bool developed many Logic ideas.

• Boolean logic deals with equations where the operators are “AND” or “OR” instead of “add” and “multiply”.

Electric Logic

• Logical values can easily be expressed by an electrical circuit.

• “True” or “1” can be defined as voltage on a wire while “False” or “0” can be defined as no voltage. We will use positive logic.

• Analog values can be anything while digital only has discrete values, 0 or 1

• Electrical devices called “gates” can implement the logical