Electronics and Gadgets Electronics is the branch of science, engineering and
technology that deals with electrical circuits involving active electrical
components such as vacuum tubes, transistors, diodes and integrated circuits,
and associated passive interconnection technologies. The nonlinear behaviour of
active components and their ability to control electron flows makes
amplification of weak signals possible and is usually applied to information and
signal processing. Similarly, the ability of electronic devices to act as
switches makes digital information processing possible. Interconnection
technologies such as circuit boards, electronics packaging technology, and other
varied forms of communication infrastructure complete circuit functionality and
transform the mixed components into a working system.
A gadget is a small
technological object that has a particular function, but is often thought of as
a novelty. Gadgets are invariably considered to be more unusually or cleverly
designed than normal technological objects at the time of their invention.
Gadgets are sometimes also referred to as gizmos.
Electronics is distinct
from electrical and electro mechanical science and technology, which deals with
the generation, distribution, switching, storage and conversion of electrical
energy to and from other energy forms using wires, motors, generators,
batteries, switches, relays, transformers, resistors and other passive
components. This distinction started around 1906 with the invention by Lee De
Forest of the triode, which made electrical amplification of weak radio signals
and audio signals possible with a non-mechanical device. Until 1950 this field
was called radio technology because its principal application was the design and
theory of radio transmitters, receivers and vacuum tubes.
Today, most
electronic devices use semiconductor components to perform electron control. The
study of semiconductor devices and related technology is considered a branch of
solid state physics, whereas the design and construction of electronic circuits
to solve practical problems come under electronics engineering. This article
focuses on engineering aspects of electronics.
An electronic component is
any physical entity in an electronic system used to affect the electrons or
their associated fields in a desired manner consistent with the intended
function of the electronic system. Components are generally intended to be
connected together, usually by being soldered to a printed circuit board (PCB),
to create an electronic circuit with a particular function (for example an
amplifier, radio receiver, or oscillator). Components may be packaged singly or
in more complex groups as integrated circuits. Some common electronic components
are capacitors, inductors, resistors, diodes, transistors, etc. Components are
often categorized as active (e.g. transistors and thyristors) or passive (e.g.
resistors and capacitors).
Most analog electronic appliances, such as
radio receivers, are constructed from combinations of a few types of basic
circuits. Analog circuits use a continuous range of voltage as opposed to
discrete levels as in digital circuits Rigid flex PCB. The number of different
analog circuits so far devised is huge, especially because a circuit can be
defined as anything from a single component, to systems containing thousands of
components. Analog circuits are sometimes called linear circuits although many
nonlinear effects are used in analog circuits such as mixers, modulators, etc.
Good examples of analog circuits include vacuum tube and transistor amplifiers,
operational amplifiers and oscillators.
One rarely finds modern circuits
that are entirely analog. These days analog circuitry may use digital or even
microprocessor techniques to improve performance. This type of circuit is
usually called mixed signal rather than analog or digital. Sometimes it may be
difficult to differentiate between analog and digital circuits as they have
elements of both linear and non linear operation. An example is the comparator
which takes in a continuous range of voltage but only outputs one of two levels
as in a digital circuit. Similarly, an overdriven transistor amplifier can take
on the characteristics of a controlled switch having essentially two levels of
output.
Digital circuits are electric circuits based on a number of
discrete voltage levels. Digital circuits are the most common physical
representation of Boolean algebra and are the basis of all digital computers. To
most engineers, the terms digital circuit, digital system and logic are
interchangeable in the context of digital circuits PCB Prototype. Most digital circuits use a
binary system with two voltage levels labeled 0 and 1. Often logic 0 will be a
lower voltage and referred to as Low while logic 1 is referred to as High.
However, some systems use the reverse definition (0 is High) or are current
based. Ternary (with three states) logic has been studied, and some prototype
computers made. Computers, electronic clocks, and programmable logic controllers
are constructed of digital circuits. Digital signal processors are another
example.
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