A

Project Stage-I Report

On

“PN JUNCTION, ZENER DIODE & LED CHARACTERISTICS”“PN JUNCTION, ZENER DIODE & LED CHARACTERISTICS”Submitted to the

Rajasthan Technical University, Kota

In partial fulfillment of the requirement for the award of the

Degree of

Bachelor of Technology

In

Electronics and Communication Engineering

Guided by: Submitted by:CP JAIN SIR 1. MEGHA MALHOTRA(13EI22)

2. MOBIN PATHAN (13EI24)3. OM PRAKASH (13EI31)4. PARAS MAL DHAKER (13EI32)

Department of Electronics and Communication Engineering

Govt. Engineering College, Ajmer

Dec, 2016

Govt. Engineering College, Ajmer (estd.1997)

(Anautonomous institute of Govt. of Rajasthan)Badliya Circle National Highway No. 8, Ajmer- 305025

www.ecajmer.ac.in Tel No. 0145- 2671801 Fax No. 0145- 2671800

CERTIFICATE

This is to certify that following students of VII Semester, B. Tech. (Electronics Instrumentation

& Control Engineering) “2016-2017”, have completed the project Stage-I titled “PNPN

JUNCTION, ZENER DIODE & LED CHARACTERISTICSJUNCTION, ZENER DIODE & LED CHARACTERISTICS” in partial fulfillment for the award

of the degree of Bachelor of Technology under Rajasthan Technical University, Kota.

1. MEGHA MALHOTRA (13EEAEI022)

2. MOBIN PATHAN (13EEAEI024)

3. OM PRAKASH (13EEAEI031)

4. PARAS MAL DHAKER (13EEAEI032)

Date: 22 DEC, 2016

Dr. C.P. JAIN AJAY DADHIACH Dr. J.K. DEEGWAL

(Guide) (Project Co-ordinate) (HOD ECE)

ACKNOWLEDGEMENT

The project Stage-I report on “PN JUNCTION, ZENER DIODE & LED CHARACTERISTICSPN JUNCTION, ZENER DIODE & LED CHARACTERISTICS”

is outcome of guidance, moral support and devotion bestowed on us throughout our work. For

this we acknowledge and express our profound sense of gratitude and thanks to everybody who

have been a source of inspiration during the project preparation.

We offer our sincere phrases of thanks with to our Project Guide Mr. Guide Name

without whose support and guidance it would not have been possible for this Project to have

materialized and taken a concrete shape.

We are thankful to Dr. J. K. DEEGWAL (HOD, EI&CE), Govt. Engineering College,

Ajmer. I would also like to express our gratitude to Mr. AJAY DADHICH (Project

Coordinator), to provide us a better facility to enhance our practical knowledge.

At last but not the least, I am thankful to all our colleagues and other staff members, who

helped us directly or indirectly in the Project work.

MEGHA MALHOTRA(13EEAEI022)

MOBIN PATHAN (13EEAEI024)

OM PRAKASH (13EEAEI031)

PARAS MAL DHAKER (13EEAEI032)

CANDIDATE’S DECLARATION

We hereby declare that the work, which is being presented in this report entitled, “PNPN

JUNCTION, ZENER DIODE & LED CHARACTERISTICSJUNCTION, ZENER DIODE & LED CHARACTERISTICS” submitted in partial fulfillment of

the requirement for the award of Degree of “Bachelor of Technology” in Electronics

Instrumentation & Control Engineering, Rajasthan Technical University, Kota, is an authentic

record of our own work carried out under the Guidance of our Project Supervisor Mr. Guide

Name, Govt. Engineering College, Ajmer.

MEGHA MALHOTRA MOBIN PATHAN

(13EEAEI022) (13EEAEI024)

OM PRAKASH PARAS MAL DHAKER

(13EEAEI031) (13EEAEI032)

TABLE OF CONTENTS

CHAPTER NO. TITLE NAME PAGE NO.

CERTIFICATE

ACKNOWLEDGEMENT

DECLARATION

1. INTRODUCTION 1

2. PN JUNCTION DIODE 2

2.1 INTRODUCTION 2

2.2 EQUILIBRIUM 3

2.3 FORWARD BIAS 5

2.4 REVERSE BIAS 7

2.5 CURRENT ACROSS DEPLETION REGION 8

2.6 CIRCUIT DIAGRAM 8

2.6.1 FORWARD BIAS 8

2.6.2 REVERSE BIAS 9

2.7 PRECAUTIONS 9

2.8 EXPERIMENT 9

2.8.1 FORWARD BIASED CONDITION 9

2.8.2 REVERSE BIASED CONDITION 10

2.9 GRAPH 10

2.10 CALCULATION FROM GRAPH 11

2.11 APPLICATION OF PN JUNCTION DIODE 11

3. ZENER DIODE 12

3.1 UNBIASED SEMICONDUCTOR DIODE 13

3.2 PRINCIPLE & WORKING OPERATION 15

3.2.1 ZENER BRACKDOWN 15

3.3 EXPERIMENT 16

3.3.1 FORWARD BIAS CONDITION 16

3.3.2 CIRCUIT DIAGRAM 17

3.3.3 REVERSE BIAS CONDITION 17

3.4 CHARACTERISTICS MODAL 18

3.5 APPLICATION OF ZENER DIODE 19

3.5.1 ZENER DIODE AS A VOLTAGE 19

3.5.2 ZENER DIODE AS A REFERANCE VOLTAGE 20

3.5.3 ZENER DIODE AS A VOLTAGE CLAMPER 21

4 LED 22

4.1 INTRODUCTION 22

4.2 WORKING PRINCIPLE 23

4.3 CIRCUIT DIAGRAM 25

4.4 EXPERIMENTAL PROCEDURE 26

4.5 CHARACTERISTICS CURVE OF LED 27

4.6 APPLICATION OF LED 27

LIST OF FIGURES

FIGURE NO. TITLE NAME PAGE NO.

1.1 PN JUNCTION APPARATUS 1

2.1 PN JUNCTION IN THERMAL EQUILIBRIUM 3

WITH ZERO BIAS VOLTAGE

2.2 A PN JUNCTION IN THERMAL EQUILIBRIUM 4

WITH ZERO BIAS VOLTAGE APPLIED

2.3 A SILICON P-N JUNCTION IN REVERSE BIAS 7

2.4 CIRCUIT DIAGRAM OF FORWARD BIAS 8

2.5 CIRCUIT DIAGRAM OF REVERSE BIAS 9

2.6 GRAPH OF FORWARD & REVERSE BIASED 10

CONDITION

3.1 SYMBOL OF ZENER DIODE 12

3.2 ZENER DIODE & ITS CHARACTERISTICS 13

3.3 CHARACTERISTICS OF UNBIASED SEMI- 14

CONDUCTOR DIODE

3.4 WORKING & OPERATION OF ZENER DIODE 16

3.5 FORWARD BIAS OF ZENER DIODE 17

3.6 REVERSE BIAS OF ZENER DIODE 18

3.7 CHARACTERISTICS MODEL 18

3.8 ZENER DIODE AS VOLTAGE REGULATOR 19

3.9 ZENER DIODE AS VOLTAGE REFERANCE 20

3.10 ZENER DIODE AS VOLTAGE CLAMPER 21

4.1 STRUCTURE OF LED 22

4.2 ENERGY DIAGRAM OF LED 25

4.3 CIRCUIT DIAGRAM OF FORWARD BIAS 26

4.4 CIRCUIT DIAGRAM OF REVERSE BIAS 26

4.5 CHARACTERISTICS OF LED 27