Digital Electronics:

This is difficult to imagine a world without digital computers nowadays. Computers are utilized in every spheres of life. Usually we communicate each other with the instantaneous electronic mails (emails), all of the transactions in the hospitals, banks, super markets, airlines, etc. are done with the help of digital computers. Computer is only one of the outcomes of the progress in digital electronics. It can be noted that even in large digital systems as computers, there are only few fundamental operations, which are repeated many times. The four most commonly utilized circuits in such systems are OR, AND and NOT Logic gates and FLIP-FLOP circuits. These Logic gates and circuits implement Boolean algebra, which was invented by G. Boole in mid 19th century. Therefore it becomes a necessity for the today's engineers to learn these mathematical equations for logical circuits along with the logic circuits.

Objectives

After studying this unit, you should be able to

• write down the symbols and truth tables for basic Logic gates; describe the Boolean identities pertaining to the fundamental operations of Logic gates; state the two De make Karnaugh maps and use them for simplifying Boolean expressions; design the basic combinatorial logic circuits,
• Describe the tristate concepts,
• draw the diagrams for basic Flip Flops, describe their operation and truth tables; understand and explain the several shift registers and counters, be familiar with the TTL and CMOS devices and circuits,
• Tabulate the various forms of memories and explain their operations, and
• Discuss the functions of Modems.