Introduction to digital electronics

 INTRODUCTION :

In the modern world of electronic, the term Digital is generally associated with a computer because the term Digital is derived from the way computers perform operation, by counting digits. For many years, the application of digital electronics was only in the computer system. But now-a-days, the digital electronic is used in many other applications. Following are some of the examples in which Digital electronics is heavily used.

• Industrial process control
• Military system
• TV games
• Communication system
• Medical equipment
• Radar
• Navigation
• Calculators
• Digital watches
• Clocks
• E-governance
• E-banking,
• Internet
• Household appliances (Ex: Washing machines, refrigerators, digital TVs)
• Computers

The music that we listen to on our CD players or iPods, the individuals dots on a computer screen, new digital TVs and most cell phone signals are coded into strings of binary digits.

Signal

Signal can be defined as a physical quantity, which contains some information. It is a function of one or more than one independent variables. Signals are two types.

• Analog Signal
• Digital Signal

Analog Signal

An analog signal is defined as the signal having continuous values. Analog signal can have infinite number of different values. In real world scenario, most of the things observed in nature are analog. Examples of the analog signals are following.

• Temperature
• Pressure
• Distance
• Sound
• Voltage
• Current
• Power

Graphical representation of Analog Signal (Temperature)

The circuits that process the analog signals are called as analog circuits or system. Examples of the analog system are following.

• Filter
• Amplifiers
• Television receiver
• motor speed controller

Disadvantage of the Analog Systems

• Less accuracy
• More noise effect
• More distortion
• More effect of weather

Digital Signal

A digital signal is defined as the signal which has only a finite number of distinct values. Digital signal are not continuous signal. In the digital electronic calculator, the input is given with the help of switches. This input is converted into electrical signal which having two discrete values or levels. One of these may be called low level and another is called high level. The signal will always be one of the two levels. This type of signal is called digital signal. Examples of the digital signal are following.

• Binary Signal
• Octal Signal
• Hexadecimal Signal

Graphical representation of the Digital Signal (Binary)

The circuit that process that digital signal are called digital system or digital circuit. Examples of the digital system are following.

• Registers
• Flip-flop
• Counters
• Microprocessors

With a digital signal, we are using an analog signal to transmit numbers, which we convert into bits and then transmit the bits. A digital signal uses some physical property, such as voltage, to transmit a single bit of information.