Digital Systems

Digital Design Digital Design is concerned with the design of

digital electronic circuits. Computers, data communication equipment, digital recording, etc.

Digital Systems Digital systems have such a prominent role in

today’s everyday life that we refer to the present technological period as the digital age

Signal: The physical manifestation of information.

Digital Systems manipulate discrete elements of information.

The set of symbols is restricted to a finite number of elements, i.e., 10 digits, 26 letters of the alphabet, and 52 playing cards.

Digital Systems Digital signals come from the nature of the

information itself or by quantization of a binary process.

Accounting information usually generates digital signals but audio has to be quantized to be recorded in a CD.

Digital Systems Some of the most popular kinds of signals use

just two discrete values, 0s and 1s. Bit: Binary digit with two possible values 1 or

0. Groups of bits (binary codes) are used to

represent more complex elements of information or symbols. Decimal numbers are represented by 4 bits.

Digital Systems Discrete Symbols are represented in digital

systems in binary form. The general purpose computer is the best

known digital system. The name digital computer comes from the

fact that they were originally designed to perform numeric computation with the set of digits.

Digital Systems Digital computers and systems became very

popular for several reasons: High Noise immunity Cost is continuously coming down. They perform operations otherwise impossible.

A digital system is an interconnection of digital modules. We require Digital Design to understand and to create these modules.

Number Systems

mm

nn

nn rararaarararara

.......... 22

1101

22

11

54321012345 . aaaaaaaaaaa5

54

43

32

21

10

01

12

23

34

45

5 101010101010.1010101010

xaxaxaxaxaxaxaxaxaxaxa

In general a number with a decimal point is represented as in the following example: