Digital electronics
Submitted by Sampali Chakraborty (Department of BCA,BATCH : 2017-2020)
Introduction:
Digital electronics deals with the electronic manipulation of numbers, or with the manipulation of varying quantities by means of numbers. Because it is convenient to do so, today's digital systems deal only with the numbers 'zero' and 'one', because they can be represented easily by 'off and 'on' within a circuit
Application:
Digital Electronics has a number of applications in so many different fields. Ranging from something as simple as the Display of your digital watch or the Count-down timer which you see at traffic signals in few countries to something as complex as Rocket Science or Quantum Computing, the applications of Digital Electronics are everywhere.
This should also get known; A digital application is different from system software that manages, integrates a computer's capabilities that serves the application. Learn more in: Laws Related to Web and Digital Application Accessibility.
Advantages of Digital Electronics:
- Digital Electroniccircuits are relatively easy to design.
- It has higher accuracy, programmability.
- Transmitted signals are not degraded over long distances.
- Digital Signalscan be stored easily.
- Digital Electronicsis comparatively more immune to ‘error’ and ‘noise’. But in case of high speed designs a small noise can induce error in signal.
- More Digital Circuitscan be fabricated on integrated chips; this helps us obtain complex systems in smaller size.
- Voltage at any point in a Digital Circuitcan be either high or low; hence there is less chance of confusion.
- Digital Circuitshave higher flexibility; we can change the functionality of digital circuits by making changes in software instead of changing actual circuit.
- Digital Circuitsare more reliable, since its output is invariant with respect to time where as in analog circuit output changes with change in environment.
- Transmission rate is higher, with wider broadband width.
Dis-Advantages of Digital Electronics:
- Digital Circuitsoperate only with digital signals hence, encoders and decoders are required for the process. This increases the cost of equipment.
- Energy consumption in digital circuit is more than analog circuit for same calculation or signal processing.
- Production of heat is more due to higher energy consumption.
- For smaller circuits Digital Circuitsare comparatively expensive.
- Real world is analogue in nature, all quantities such as light, temperature, sound etc. For Digital Systemsit is required to translate a continuous signal to discrete which leads to small quantization errors. To reduce quantization errors large amount of data needs to be stored in Digital Circuit.
- Portability of digital circuit is difficult.
Conclution:
A digital circuit is typically constructed from small electronic circuits called logic gates that can be used to create combinational logic. Each logic gate is designed to perform a function of boolean logic when acting on logic signals. A logic gate is generally created from one or more electrically controlled switches, usually transistors but thermionic valves have seen historic use. The output of a logic gate can, in turn, control or feed into more logic gates.
Another form of digital circuit is constructed from lookup tables, (many sold as "programmable logic devices", though other kinds of PLDs exist). Lookup tables can perform the same functions as machines based on logic gates, but can be easily reprogrammed without changing the wiring. This means that a designer can often repair design errors without changing the arrangement of wires. Therefore, in small volume products, programmable logic devices are often the preferred solution. They are usually designed by engineers using electronic design automation software.