The student expresses gratitude to the school principal and physics teacher for their guidance and support in completing a school project on logic gates. The document then provides an introduction to logic gates, including their truth tables and applications. It proceeds to describe the basics of OR, AND, NOT, NOR and NAND gates through their circuit diagrams and boolean expressions. The conclusion states that logic gates are idealized physical devices that perform boolean functions and produce single outputs based on inputs. They are useful whenever multiple events need to be detected or actions taken based on their occurrence.

2. ACKNOWLEDGEMENT
I wish to express my deep gratitude and
sincere thanks to the school Principal, Mr.
Shyam babu shukla for his encouragement and
provided facilities for this school project. I
sincerely appreciate his generosity by taking
me into his fold for which I shall remain
indebted to him. I extent my appreciation to Ms.
Archana ma’am, our physics teacher who
guided me to the successful competition of this
project. I take this opportunity to express my
deep sense of gratitude to her invaluable
guidance, ongoing encouragement, enormous
motivation, which has sustained my efforts at
all the stages of project development.

3. CONTENT
•INTRODUCTION
•THEORY
•BASICGATES
o ORgate
o ANDgate
o NOT gate
•NORgate
•NANDgate
•CONCLUSION
•BIBLIOGRAPHY

4. INTRODUCTION
GATE:-
A gate is defined as a digital circuit which
follows some logical relation ship between the
input and output voltages. It is a digital circuit
which either allows a signal to pass through or
stop the signal.
TRUTHTABLE:-
A logic gate may have one or more than one
inputs, But it has only one output.The
relationship between the possible values of
input and output voltages are expressed in the
formof a table called Truth table
BOOLEANALGEBRA:-
The algebra which is based on binary nature of
logic gates.
BOOLEANEXPRESSIONS:-
They are logical statement which are followed by
logical statement.

5. PRINCIPLEOF LOGICGATES
In this digital world of electronics, the
information is stored in the form of bits
(Binary). Certain arithmetical operations like
addition, subtraction, multiplication, and
division are to be performed on these
bits. The combination of ‘Arithmetic
Operation’ with certain ‘logic’ using binary
numbers was established by Leibniz. Further,
the electrical circuits of switching based on
vacuum tubes were designed. The invention
of relays replaced the ‘vacuum tubes’ in
switching circuits. Finally, all the inventions
lead to the destination of the logic gate.
As there was a step by step revolutions in
digital electronics, Konrad Zuse is the man
who was behind the development and the
design of ‘Electrochemical Logic Gate’. The
‘Boolean Algebra’ and the switching operation
from then on were carried out by the logic
gates.

6. Basic Gates
The OR Gate: -
It is a device that combines A and B to give Y as the
result. The OR gate has two or more inputs and one
output . In Boolean algebra, addition symbol (+), is
referred as the OR.
The Boolean expression: A+B=Y
This indicates that Y equals to A or B.
TRUTH TABLE

7. The ANDGate: -
It isa device that combinesAwith Btogive Y asthe
result. The ANDgate hastwoor more inputsand one
output . In Boolean algebra, multiplication sign isreferred
asthe AND.
The Boolean expression: A.B=Yor AXB=Y
Thisindicatesthat Y equalstoAand B.
TRUTHTABLE

8. The NOT Gate: -
It isa device that invertsthe inputs.The NOT hasone input
and hasone output . In Boolean algebra, bar symbol is
referred asthe NOT.
The Boolean expression: Z=A’
Thisindicatesthat Zisnot equal to A.
TRUTHTABLE

9. The NOR Gate
Aim:
TO DESIGN AND STIMULATE THE
NOR GATE CIRCUIT.
Component:
Two ideal p-n junction diode (D1 and D2).
An ideal n-p-n transistor
Theory and Construction:
If we connect the output Y’ of OR gate to the
input of a NOT gate, then the gate obtained is the
NOR gate. The output Y is voltage at C with
respect to earth.
In Boolean expression, the NOR gate is expressed
as:

10. The following inference can be easily drawn
fromthe working of electrical circuit:
(i) If the switch Aand Biskept open (A=0,
B=0) then bulb glows, hence Y=1.
(ii) If the switch Aiskept closed and Biskept
open (A=1, B=0) then the bulb glows,
Hence Y=0.
(iii) If the switch Aiskept open and Biskept
closed (A=0, B=1) then the bulb doesnot
glow, hence Y=0.
(iv) If the both switch Aand Bare kept closed
(A=1, B=1) then bulb doesnot glow, hence
Y=0.

11. The NAND Gate
Aim:
TO DESIGN AND STIMULATE THE NAND
GATE CIRCUIT.
Components:
Two ideal p-n junction diode (D1 and D2)
A resistance R
An ideal n-p-n transistor
Theory and Construction:
If we connect the output Y’ of the AND gate to
the input of a NOT gate then the gate obtained
is the NAND gate. The output Y is voltage at C
with respect to earth.
In Boolean expression, the NAND gate is expressed as:

12. The following inference can be easily drawn
fromthe working of circuit:
(i) If the switch Aand Bare kept closed (A=0,
B=0) then bulb glows, hence Y=1.
(ii) If the switch Aiskept open and Biskept
closed (A=0, B=1), then bulb glows, hence
Y=1
(iii) If switch Aiskept closed and Biskept
open (A=1, B=0), then bulb glows, hence
Y=1
(iv) If both switch Aand Bare kept closed
(A=1, B=1) then bulb doesnot glow, hence
Y=0.

13. CONCLUSION
INELECTRONICS, ALOGICGATEISANIDEALIZED
OVERPHYSICALDEVICEIMPLEMENTINGA
BOOLEANFUNCTION,THAT IS, IT PERFORMSA
LOGICALOPERATIONONONEORMORELOGICAL
INPUTSANDPRODUCESASINGLELOGICAL
OUTPUT,DEPENDINGONTHECONTEXT THETERM
MAY REFERTOANIDEALLOGICGATEORIT MAY
REFERTOANON-IDEALPHYSICALDEVICE.
WHENEVERTHEOCCURRENCEOFONEORMORE
THANONEEVENT ISNEEDEDTOBEDECTEDOR
SOMEACTIONSARETOBETAKENAFTERTHEIR
OCCURRENCE,INALLTHOSECASESORGATE
CANBEUSED.THEREAREMAINLY TWO
APPLICATIONSOFANDGATEASENABLEGATE
ANDINHIBIT GATE.NOT GATEINVERT THE
OUTPUT GIVENTOTHEMANDSHOWTHE
REVERSERESULT.

14. BIBLIOGRAPHY
WWW.GOOGLE.COM
HELPFORMMY TEACHERS
WWW.WIKIPEDIA.COM
I HAVETAKENHELPFORMSOMEBOOKS
THANK
YOU

15. BIBLIOGRAPHY
WWW.GOOGLE.COM
HELPFORMMY TEACHERS
WWW.WIKIPEDIA.COM
THANK
YOU