BASIC ELECTRONIC COMPONENTS
|
|
1.
Active elements
2.
Passive elements
Active elements
Element which
generates or produces electrical energy of their own are called active
elements. Example: Batteries, generators, transistor etc.
Passive elements
All elements
which do not produce energy of their own, but consumes from active elements are
called passive elements, like resistor, capacitor and inductor.
Different Components used in Electronics
Following are the
basic components used in electronics circuit. They are:
1. Resistor
2. Capacitor
3. Inductor
4. Diode
5. Transistor
6. Transformer
7. Fuse
1.
Resistor
A resistor is an electrical component that
limits or regulates the flow of electric current in an electronic circuit. It
is denoted by R. The unit of resistance is ohm Ω.
Resistor Color Coding
There
are two types of resistors.
1. Fix Resistor
2. Variable Resistor
Resistor
Connectivity
1. Resistor in series – Path of the current is same and single.
The effect of resistors in series is
additive. There is a corresponding voltage
drop across each resistor.
2. Resistor in Parallel – Current path is more than one.
For resistors in parallel, the same voltage
occurs across each resistor and more than one path exists for the current,
which lowers the net resistance.
2. Capacitor
Capacitance
·
Capacitance is the property of
a circuit or device,
which enables it to store
electrical energy
by means of an electrostatic field.
·
A device especially designated
to have a certain value of capacitance is called a capacitor.
·
The capacitor has the ability
to store electrons and release then at a later time.
·
The number of electrons that it
can store for a given applied voltage is measure of its capacitance.
Types
of Capacitors
3.
Mica Capacitor 4. SMD (Surface Mount Device) Capacitor
3.
Inductor
a coiled conducting wire wound around a core.
A current flowing through the device, produces a magnetic
flux φ forms closed loops threading its coils.
A single inductor in a circuit will have a given amount of
inductance or opposition to a change in current flow.
If another inductor of the same value is placed in parallel with the
first inductor, the amount of inductance in the circuit decreases.
The reason for this is relatively simple. Each of the inductance
still opposes the change in current through the circuit.
However, because there are now two current paths, total current
increases. Therefore, there is an overall decrease in opposition to change.
Symbol of inductor is shown beside in image.
4.
Diode
·
A device which only allows current
to flow in one direction.
·
A special diode which is used
to maintain a fixed voltage across its terminals.
A diode can be considered to be an electrical one-way valve. They are made from a large variety of materials including silicon, germanium, gallium arsenide, silicon carbide
Type of diode
1. PN Diode 2. Zener Diode
Biasing
The process of applying an
external voltage is called as “biasing”. There are two ways in which we can
bias a PN junction diode.
1) Forward bias 2) Reverse
bias
The basic difference between a
forward bias and reverse bias is in the direction of applying external voltage.
The direction of external voltage applied in reverse bias is opposite to that
of external voltage applied in forward bias.
1. Forward Bias
1. The figure
above shows a dc source across a diode. The negative source terminal is
connected to the n-type material, and the positive terminal is connected to the
p-type material.
2. This
connection Figure is called forward bias.
3. Current flows
easily in a forward-biased silicon diode.
2. Reverse Bias
4. Turn the dc
source around and you reverse-bias the diode as shown in Figure 2.
5. This time, the negative battery terminal is connected to the p side, and the positive battery terminal to the n side. This connection is called reverse bias.
5.
Transistor
Type
of the Transistor
1. PNP Transistor
2. NPN Transistor
A PNP transistor is composed of two P-type
semiconductors separated by a thin section of N-type as shown in Figure.
Similarly, NPN transistor is composed of two Ntype semiconductors separated by
a thin section of P-type as shown in figure. The symbol used for PNP and NPN
transistors are also shown with the diagrams.
2. PNP
Transistor
6.
Transformer
"Rate of change of flux linkage with respect to time is directly proportional to the induced EMF in a conductor or coil".
Basic
Theory of Transformer
Say you have one winding which is supplied
by an alternating electrical source. The alternating current through the
winding produces a continually changing flux or alternating flux that surrounds
the winding. If any other winding is brought nearer to the previous one,
obviously some portion of this flux will link with the second. As this flux is
continually changing in its amplitude and direction, there must be a change in
flux linkage in the second winding or coil. According to Faraday’s law of
electromagnetic induction, there must be an EMF induced in the second. If the
circuit of the later winding is closed, there must be current flowing through
it. This is the simplest form of electrical power transformer and this is the
most basic of working principle of transformer.
The winding which takes electrical power from the source, is generally known as primary winding of transformer. Here in our above example it is first winding.
The winding which gives the desired output
voltage due to mutual induction in the transformer, is commonly known as
secondary winding of transformer. Here in our example it is second winding.
The above mentioned form of transformer is theoretically possible but not practically, because in open air very tiny portion of the flux of the first winding will link with second; so the current that flows through the closed circuit of later, will be so small in amount that it will be difficult to measure.
7.
Fuse
Fuses are current-sensitive devices that provide reliable protection for discrete components or circuits by melting under current overload conditions. Choosing the right fuse for your application can be an overwhelming, time-consuming process, even for a seasoned electronics design engineer. This user-friendly Fuse ology Selection Guide makes the fuse selection process quick and easy helping you optimize the reliability and performance of the application.
Purpose
of Fuses
·
Circuit protection is critical,
and in many cases required, in electrical and electronic products.
·
Fuses are an inexpensive and
effective way to protect your device from damage due to overcurrent conditions.
·
Fuses can prevent safety
hazards to the end user such as fire and catastrophic failure of the product.
No comments:
Post a Comment