ELECTRONICS AND SEMI CONDUCTOR
Electronics and semiconductor
Electronic is a system that controls the flow of electrons or any other charge carriers like vaporized materials of electrodes in semiconductors. The study of semiconductor devices and their control by electronic system is a branch of the study of physics.
Electronic circuits
Electronic circuits are used for multifarious purposes.
The two most important fields are: -
1. conversion and distribution of electric powers, and
2. Controlling and processing of information.
Developments in electronic technology have been instrumental in replacing old day electric current based systems of telegraph and telephone.
Electronic system
The three basic parts of electronic system are: -
1. Inputs
2. Signal processors, and
3. Outputs.
All of the above are electronic circuits. The input electronic circuit receives signals from sending sources and converts them into current, voltage or digital signals. The Signal processor circuits interpret and transform the input signals to digital signals. The output circuits transform the said signals back into original physical form. In a television set, the input signal is received, converted into broadcast signals, and further converted into visible and audible signals for users to enjoy.
Electronic component
Electronic components are ordinarily provided in packages with two connecting devices that may be shouldered into a printed circuit board. This creates an electronic circuit with a particular function. An amplifier is a good example of such a component. Sometimes these components are combinations of a number of electronic circuits as in case of a radio receiver. Digital electronic circuits are ordinarily based on Boolean algebra and a number of discrete voltage levels. Computers always use digital circuits.
Semiconductor
Any material that has electrical conductivity ranging between a conductor and an insulator is called a semiconductor. The semiconductor characteristic of any material is determined by its electronic band structure. When the temperature is low, the semiconductor may also work as insulator. Even at room temperature, the electrical conductivity of a semiconductor remains lower than a conductor. Elements like silicon and compounds like aluminum gallium are all a specimen of a semiconductor. The electronic band structure has a bad gap between the topmost band, i.e., valence and the next level of valence electrons. The semiconductor differs from an insulator in that the band gap in semi conductor is smaller than the insulator.
Doping and semiconductor
Electronic properties of a semiconductor can be modified by the introduction of impurities in the material. This process of introducing impurities in a semiconductor is called “Doping”. Examples of such doped semiconductors are diodes and bipolar junction transistors. The electronic fields of a semiconductor can also be altered using applied electrical or magnetic fields from outside the semiconductor. Examples of this type of semiconductors are Hall Effect sensors and insulated gate field effect transistors.
|
