Engineering perhaps more than any other field of technology, has an explosive development in the last four decades. Electronic devices and circuit design is a broad discipline. This is a first course in electronics for electrical engineers. It should be of interest to physics majors and to practicing engineers and scientists who wish to update their knowledge of semiconductor electronics and of integrated circuits. Design is a kind of creative activity that begins with a definition of the problem to be solved or specification of the device to be built. Solving the problem or specifying the device in enough detail to build it is the goal of the designer.
Objective of the course:
The objective of this subject is to develop in the student the ability to analyze and design electronic circuits, both discrete and integrated. In 1960’s these circuits were implemented using Vacuum Tubes. Later in the 1970’s the electronic design depended on integrated circuits where emphasis is placed on transistor and FET circuit designs. In this subject the reader is taken step-by-step from semiconductor physics to devices, models, circuits and systems.
* Every semiconductor device like the p-n diode, the breakdown diode, the tunnel diode, the light-emitting diode, the bipolar junction transistor (BJT), junction field-effect transistor (JFET), the metal-oxide-semiconductor field-effect transistor (MOSFET) and integrated resistors and capacitors is considered in this subject.
* The amplification of weak signals into stronger signals is of fundamental importance in any electronic system. So the design of amplifiers using transistor, FET and operation amplifier is introduced under this title.
* In almost all the communication transmitters and receivers, there is a requirement feedback amplifier, oscillators, filters which are brought under this subject.
* Circuits with discrete components occupies more space, in order to introduce the concept of portability integration of components to a single substrate is also introduced at the second year level for circuit engineering branches. This is done because of our belief that the majority of those studying the subject were to pursue a career in IC design; knowledge of what is inside the IC package would enable intelligent and innovative application of chips.
* Furthermore, with the advances in VLSI technology and design methodology, IC design is becoming accessible to an increasing number of engineers.
The field of electronics is so broad that all human endeavors involve some form of electronics application. The following are a few of the innumerable areas that are dependent on electronics.
Information, Communications and Entertainment : The progress of a country depends upon the availability of economical and rapid means of communication. These electronic circuits find extensive application in such fields as computers, counting and timing systems, data-processing systems, pulse communications, radar telemetry, television and in many areas of experimental research.
Transportation : In this jet age of travel, electronics is used in supersonic aircrafts to bullet trains to even a musical horn in a bicycle. Navigation of ships, space shuttles, air and auto traffic control, global positioning systems and so on are all electronic.
Medicine : Electronics and biomedical instrumentation have a huge role in this key field of medicine. Diagnostics such as ECG, MRI and X-ray; electronic microscope, scanning, cancer treatment, surgery, patient monitoring, treatment; therapies such as laser, ultrasound and electronic puncture; rehabilitation aids and technique such as pacemakers, drug delivery, physical therapy and biofeedback; patient aids such as artificial limbs and hearing aids; biomedical instrumentation, telemedicine and many more are all electronic.
Instrumentation: Automation in industries is the order of the day. Electronic gadgets control the process of production in an industry, whatever may be the type of product. Industrial heating, welding, power device controls, and so on are also electronic. Cathode-ray oscilloscopes, ammeters, voltmeters, digital and analog multimeters, flux meters, pH meters, strain gauge, and precision measuring equipment are a few more examples of electronic instrumentation.
Scientific research : Electronics make scientific research simple by means of simulations, modeling and so on.
Environmental protection : Electronics find application in the protection of environment also. Electronic alarms can be employed which alert when a specified level of pollution is exceeded. Electric car, the recent invention, emits minimum or no pollutants into air. Waste treatment or waste water recycling is all controlled by electronic gadgets.
Military : Defense operations currently are largely electronic. The radar gives the exact coordinates and tracks the target with extreme precision. The missiles are guided by electronic equipment. Global positioning systems give exact enemy location. Secrecy of information is achieved these days with the help of digital communications. To maintain the secrecy of base military camps and stations, electronic countermeasures, electronic jammers and so on are employed.
Computers: All hardware circuits and modules of digital computers such as CPU, monitors, keyboard, printers, scanners, CD writers, players, floppy drives, memory—RAM or ROM, uninterrupted power supplies and webcams are all electronic. Hardware components of LAN, MAN, WAN of various computing systems, e-mail, e-chat, all networking modems, modules, robots, computer communications, data communications, e-commerce, e-business, e-transcription, e-manufacturing and e-banking (for example, credit cards and ATMs) make use of the principles of electronics.
Education : Education at present employs large amount of electronics. E-learning and satellite TV form an integral part of distance-mode education system. Even for classroom teaching one requires LCD projectors, slide projectors, PA systems and so on, which are all electronic.
Astronomy : The space shuttle and its control, the communication gadgets employed in the study of extraterrestrial features of space, other planets, moon and so on are all electronic.
Home : Every nook and corner of a modern house is stacked with electronic gadgets. Electronic devices have simplified and speeded up mundane tasks of cleaning, cooking, lighting and security. Recreation at home is essentially the electronic way. Microwave oven, telephone, answering machine, home security, personal computer, light dimmers, appliances, toys, air conditioners, refrigerators, watches, clocks, washing machines, grinders, vacuum cleaners, electronic regulators, digital cameras, movie and video cameras and so on are few of the electronic devices used in the present day homes.
The subject Electronic Devices and Circuits is introduced at Ist or IInd years of Engineering education in almost all state and central level Universities. Competitive examinations such as GATE, NET, DRDO, IES, JTO and public sectors like ONGC, Nalco, HAL, BHEL, Power Plants, Steel Plant etc will cover this subject in the entry level examinations and at technical interview.
Dr. P.V.Y. Jayasree
Department of ECE