Digital Electronics

Digital Electronics

Digital electronics  are electronics that handle digital signals

In most cases, the number of these states is two, and they are represented by two voltage bands: one near a reference value (Ground or zero volts), and the other a value near the supply voltage . These correspond to the false(0) and true (1) values of the Boolean domain respectively, named binary code.

Digital techniques are useful because it is easier to get an electronic device to switch into one of a number of known states than to accurately reproduce a continuous range of values.

Digital electronic circuits are usually made from large assemblies of logic gates, simple electronic representations of Boolean logic functions

Advantages of Digital Electronics

An advantage of digital circuits when compared to analog circuits is that signals represented digitally can be transmitted without degradation due to noise. 

In a digital system, a more precise representation of a signal can be obtained by using more binary digits to represent it. While this requires more digital circuits to process the signals, each digit is handled by the same kind of hardware, resulting in an easily scalable system. In an analog system, additional resolution requires fundamental improvements in the linearity and noise characteristics of each step of the signal chain.Computer-controlled digital systems can be controlled by software, allowing new functions to be added without changing hardware. Often this can be done outside of the factory by updating the product's software. So, the product's design errors can be corrected after the product is in a customer's hands.Information storage can be easier in digital systems than in analog ones.

Digital circuits are sometimes more expensive, especially in small quantities.

 

Structure of Digital systems

Engineers use many methods to minimize logic functions, In order to reduce the circuit's complexity. When the complexity is less, the circuit also has fewer errors and less electronics, and is therefore less expensive.

The most widely used simplification is a minimization algorithm like the binary decision diagrams, an automated Quine–McCluskey algorithm, truth tables, Karnaugh maps, and Boolean algebra have been used.

Representation Of Digital Systems

To choose representations, Scientist consider types of digital systems. Most digital systems divide into "combinational systems" and "sequential systems."

A combinational system always presents the same output when given the same inputs. It is basically a representation of a set of logic functions.

A sequential system is a combinational system with some of the outputs fed back as inputs. This makes the digital machine perform a "sequence" of operations. The simplest sequential system is probably a flip flop, a mechanism that represents a binary digit or "bit".

Sequential systems divide into two further subcategories.

 "Synchronous" sequential systems change state all at once, when a "clock" signal changes state. "Asynchronous" sequential systems propagate changes whenever inputs change.