Electronics Mini projects
CircuitsToday is listing some free
engineering mini projects that can be presented and designed by students
for their exams. These mini projects are applicable for B-Tech/BE
engineering students from various streams like Electronics and
Instrumentation (EI), Electronics and Communication (ECE), Electrical
Engineering (EEE), diploma and so on. Though the electronic circuits may
look complex, they are explained in detail along with a circuit
diagram, and are explained with links of all devices that are used in
the circuit. Please note that these projects are meant for students,
hobbyists and enthusiasts. If there are any doubts regarding the
circuit, feel free to comment on the post. You can also bring in any
modifications you want, and ask us if you have doubts. Furthermore,
please go through the existing comments to get a better idea of the
electronics mini project topics.
This minor mini project is used to
design a street light that brightens up when night falls and
automatically turns OFF when day light comes in. In order to detect the
amount of light that is needed to decide when to cut-off the circuit and
later activate it is done with the help of a sensor called Light Dependent Resistor (LDR).
The main principle used behind the LDR is that, the presence of light
causes the resistance of the sensor to go low. You can modify he circuit
by placing LED’s instead of the 230 volt lamp. To know more about it,
check out the comments given in the circuit. The circuit is
comparatively easy to design, and further modifications can be made
according to your choice.
This is one of the most basic and best mini projects in electronics. A Silicon Controlled Rectifier (SCR)
is used to rectify the AC mains voltage to charge the battery. The
circuit consists of basic transistor switching methods and the
components are cheap and are available in all electronics shops. A
detailed description about the post is also given, which will give you a
better idea.
This simple mini project is used to
design an indicator to show the rate of air flow in a given space. The
air flow is sensed with the help of an incandescent bulb filament. The
variations due to the change of resistance in the bulb due to the air
flow are given to the input of an LM339 operational amplifier.
The circuit diagram and a better description of the circuit is given in
the post above. Further modifications can be brought to the circuit and
some of them are given in the comments section.
This circuit is used to produce an alarm
output (bell or light), when the level of water rises above a certain
level. This circuit uses a basic astable multivibrator made from a 555 timer IC.
A resistance probe is set on a point at which the alarm is to set ON,
as soon as the water rises up to that level. A detailed circuit can be
seen in the post above. The number of components needed for this circuit
is very less and can be easily assembled on a PCB.
This circuit can be used for detecting a
fire and producing an alarm, thus alerting the people in the building
where it is installed. A transistor sensor called BC177 is used to sense
the heat produced due to the fire. A preset level can be kept for the
transistor. As soon as the temperature rises above the set preset level,
the leakage current of the transistor rises, thus driving the other
transistors in the circuit. A relay
is also used to switch the bell load as its output. The components
needed for the circuit can be obtained easily and the circuit is easy to
design.
This mini project is mainly meant for
Btech EC students. An IC called TDA7000 is used for the purpose. The IC
is integrated with a Frequency-Locked-Loop system with an intermediate
frequency of 70 kHz. There have been many complaints that the IC is
obsolete. Please check the comments to know the exact site to buy the
IC. For more detailed explanation about the FM radio circuit, please check out the original post.
The project consists of a digital watch
designed with the help of a 555 timer IC and 4-bit digit counter IC
called IC MM&4C926, and also a 7 segment LED
display. The circuit can be easily designed and assembled on a printed
circuit board. Further instructions and detailed working can be obtained
from the original post.
This circuit can not only be presented
as your mini project, but can also be applied on your home electrical
equipments to protect them from over voltage fluctuations. The circuit
requires very simple components like a monostable multivibrator using a 555 timer, a few transistors, and some diodes, relays ad LED.
The detailed explanation is given in the
post above, and if you wish you can easily modify the circuit to make
it an automatic voltage stabilizer.
This circuit uses an LM 311 comparator
IC and a light dependent resistor as its sensor. The output of the LDR
is given to the inverting input of the comparator. The resistance
remains high when there is no light and the resistance drops as soon as
light falls on it. This lessens the voltage at the inverting input and
thus the comparator produces a high output which turns a transistor and
thus the relay on. A much more detailed working can be obtained from the
original post.
This circuit can be used to escape from
the nuisance of mobile phone rings when you are at home. This circuit
will give a visual indication if placed near a mobile phone even if the
ringer is deactivated.
Latest Mini Projects:-
This is a classic mini project for
electronics engineering students. Developed using AT89S51 (a version of
8051 from Atmel) with a well explained circuit diagram and program. We
have tested and verified this circuits functioning in our lab. The
program is written in assembly language using the MCS-51 instruction
set.
In this project, you can make a
frequency counting device/system.We have developed this using Avr
Atmega8 microcontroller. We have given the complete circuit diagram,
software codes and other necessary information to make this project a
reality. If you are not familiar with Avr Atmega8 controller, we have
developed a complete tutorial to learn Avr from ground.
Note:- If you have any doubts, please ask in the comments section of the corresponding post
In this project, you can make a simple
digital voltmeter application which can measure upto 5 volts (0 to 5
volts). The circuit is developed using ADC0804 and AT89S51 micro
controller. The output is displayed using two 7 segment displays. The
software is developed in assembly language.
