In modern world of electronics the term “Digital” is generally associated with computer. This is because the term “Digital” is arrived from the way computer performs operation i.e. by counting digits. If you take a look around then you will find that the use of electronics and technology is significantly increasing. The need for electronics has increased and even the technology has become much advance which makes the task easy. The involvement of digital technology is a great deal for high power and high risk tasks where human involvement cannot be risked.
The Digital Electronics is a technology that generate, stores and posses the data in terms of two states : 1) Positive and 2) Non Positive. The positive state refers to number 1 and negative state refers to number 0. Hence the data transfer in digital systems is expressed as strings of 0’s and 1’s. Now each of this state digits are referred to as “bits” and the string of bits is called as “bytes”. The use of analog electronics was much complex as it conveys the data as electric signals with varying frequency and amplitude and mixes it with given carrier, but the use of digital system is much more simple.
Evolution Of Digital Electronics :
In the beginning in around 1930’s the electrical circuits of computers were designed using mechanical switches and relays which were very slow and large and produced large amount of heat. Further in 1940’s the switches and relays were replaced by diodes and transistors which were much faster, cooler and smaller in size, but they were irreliable. To overcome this problem the diodes and transistors were then replaced by digital component called IC’s.
Comparison Of Analog And Digital System :
Analog Circuits Digital Circuits
These circuits operate on continuous valued signals(commonly referred to as analog signals). These circuits operate on signals that exist only at two levels i.e. 0’s and 1’s (binary number system).
Analog circuits are difficult to design since each component has to be placed by hand as automation techniques for designing these circuits fail to do the job efficiently. On the other hand digital circuits are easy to design since automation technique can be applied at various levels of circuit design. This involves minimum human interaction.
No conversion of input signals are required before processing i.e. input signal is analog, the circuit directly performs various logical operations and produces an analog output. In digital circuits, the input signals are converted from analog to digital form before it is processed, i.e. the digital circuit is capable of processing digital signals only, and produces output which is again converted back from digital to analog signals so that the output gives meaning full results that can be understood by humans.
In analog circuits, since there are no conversions involved at the input or at the output side there is no loss of information that is available for processing. Due to the conversion process at the input side(analog to digital) and at the output side, some amount of information is lost during the conversion process.
The man power available to design analog circuits is very low, this results in long time to market the finished products. The available man power to design digital circuits is significantly large compared to that of analog circuit designers.
Analog circuits are mostly custom made and lacks flexibility. Digital circuits have high degree of flexibility.
Advantages Of Digital Electronics :
Signal can be transmitted without degradation.
Signal can be reconstructed without error.
Digital system is more precise and easy to use.
Information storage is easier in digital system.
Disadvantages Of Digital Electronics :
Requires greater bandwidth than analog system.
Sampling error occurs.
Synchronization is required.
Popular Books On Digital Electronics :
1) Digital system engineering : William.J.Dally.
2) Digital system design(e book) : Bookboon.