Design And Construct Of 1.5W Power Amplifier

An amplifier is an electronic device that increases the voltage, current, or power of a signal. Amplifiers are used in wireless communications and broadcasting, and in audio equipment of all kinds. They can be categorized as either weak-signal amplifiers or power amplifiers. The most frequently-used device for power amplification is the bipolar transistor. In this work we are focusing on direct couple amplifier is also one of the transistor based amplifier in which the output of one stage of the amplifier is coupled to the input of the next stage in such a way as to permit signals with zero frequency,

TABLE OF CONTENTS

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

1.0      INTRODUCTION

1.1      BACKGROUND OF THE PROJECT

1.2      PROBLEM STATEMENT

1.3      OBJECTIVE OF THE PROJECT

1.4     APPLICATION OF THE PROJECT

1.5      SIGNIFICANCE OF THE PROJECT

1.6      LIMITATION OF THE PROJECT

1.7      SCOPE OF THE PROJECT

1.8      METHODOLOGY

1.9      PROJECT ORGANISATION

CHAPTER TWO

2.0     LITERATURE REVIEW

2.1      OVERVIEW OF AMPLIFIER

2.2      HISTORITICAL BACKGROUND OF AN AMPLIFIER

2.2      OVERVIEW OF DIRECT-COUPLED AMPLIFIER

2.3     IMPORTANT CHARACTERISTICS OF AN AMPLIFIER

2.4      TYPES OF AMPLIFIERS

2.5      TYPES OF POWER AMPLIFIERS

CHAPTER THREE

3.0     METHODOLOGY

3.1      BLOCK DIAGRAM

3.2     CIRCUIT DIAGRAM

3.3     CIRCUIT OPERATION

3.4     CIRCUIT DESCRIPTION

CHAPTER FOUR

RESULT ANALYSIS

4.0      CONSTRUCTION PROCEDURE AND TESTING

4.1      CASING AND PACKAGING

4.2      ASSEMBLING OF SECTIONS

4.3      TESTING OF SYSTEM OPERATION

CHAPTER FIVE

5.1      CONCLUSION

5.2      RECOMMENDATION

5.3      REFERENCES

CHAPTER ONE

1.0                                                        INTRODUCTION

1.1                                                  BACKGROUND OF THE

An Amplifier circuit can be described as, a circuit which is used to increase the input signal. But, not every amplifier circuit is the same due to their type of circuit configuration as well as operation. In electronic circuits, a small signal amplifier can be used because it amplifies a small input signal. There are different types of amplifier circuits like operational amplifiers, power amplifiers, and small signal to large signal amplifiers. The amplifiers classification can be done based on the signal size, configuration and process of the input signal which means the relationship among the flow of current within the load as well as an input signal. This work discusses an overview of DC amplifiers [1].

A DC amplifier (direct coupled amplifier) can be defined as is a kind of amplifier where the one stage output of the amplifier can be connected to the next stage input for allowing the signals without frequency. So this is named as the direct current which passes from input to output. The DC amplifier is another type of coupling amplifier and this amplifier is particularly used for amplifying low-frequencies like thermocouple current otherwise photoelectric current [3].

This type of amplifier can be used for both DC (direct current) signals as well as AC (alternating current) signals. The DC amplifier’s frequency response is the same as LPF (low pass filter). The direct current amplification can be achievable only by using this amplifier, therefore later it turns into the basic building block of the differential as well as operational amplifier. In addition, monolithic IC(integrated circuit) technology does not permit the production of large coupling capacitors [1][2][3].

1.2                                             OBJECTIVE OF THE PROJECT

The main objective of this work is to build an amplifier in which the output of one stage of the amplifier is coupled to the input of the next stage in such a way as to permit signals with zero frequency, also referred to as direct current, to pass from input to output whose power is rated 1.5w.

1.3                                         SIGNIFICANCE OF THE PROJECT

The advantages of the amplifiers include the following.

1. This is a simple circuit and can be designed a minimum number of basic electronic components
2. It is inexpensive

• This amplifier can be used to amplify low-frequency signals

1.4                                           LIMITATION OF THE PROJECT

As we all know that no human effort to achieve a set of goals goes without difficulties, certain constraints were encountered in the course of carrying out this project and they are as follows:-

1. Difficulty in information collection: I found it too difficult in laying hands of useful information regarding this work and this course me to visit different libraries and internet for solution.
2. Difficulty in parts gathering: I found it too difficult when gathering electronics parts used for the prototype.

• Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).

1.5                                         APPLICATIONS OF THE PROJECT

The applications of this amplifier include the following [4][5].

1. The applications of DC amplifiers include computers, regulator circuits¸ TV receivers, and other electronic devices.
2. This amplifier can build differential amplifiers as well as operational amplifiers.
3. These amplifiers can be used in pulse amplifiers, differential amplifiers,

These amplifiers can be used in controlling of Jet engine, regulators in power supply. etc

1.6                                                   SCOPE OF THE STUDY

The amplifier circuit can be operated without using capacitors, transformer, inductor, etc which is known as frequency sensitive components. This amplifier amplifies the AC signal by low frequency. Whenever we applied a positive half cycle at the input of the primary transistor Q1. This transistor is already biased with the help of the divider bias network. The applied half cycle can make the Q1 transistor forward biased to start the conduction & provide an amplified and inverter output the collector terminal [4][5].

1.7                                                  RESEARCH QUESTIONS

1. How does an amplifier work?
2. What is an amplifier?

1.8                                                        METHODOLOGY

To achieve the aim and objectives of this work, the following are the steps involved:

1. Study of the previous work on the project so as to improve it efficiency.
2. Draw a block diagram.

• Test for continuity of components and devices,

1. Design and calculation for the amplifier was carried out.
2. Studying of various component used in circuit.
3. Construct the amplifier circuit.

• Finally, the whole device was cased and final test was carried out.

1.7                                                         PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.