Design And Construction Of A Two-digit Digital Counter

ABSTRACT

In this work, we designed and constructed a digital counter circuit. The initial design criteria for the project were: to have a two digit output, to have the circuit count from 0-99, to include either a 555 timer or manual counter. Research was conducted into similar analogue electronic circuits and a suitable point of a digital die was identified. The digital counter circuit was designed using BCD 4506 binary counters and 7-segment display outputs. The circuit was modeled using proteus, which showed that the concept used in the design was okay. The circuit was then implemented and tested on a bread board before transferring it to a mother board. There are two modes of operation of the circuit: through manual switch which increments on its push, and through a 555 clock which increments automatically. In the end we were able to design and construct a two-digit, digital counter that was able to count between 0-99 using a 4026IC, shadow sensor and a 555 timer. The input clock pulses were from shadow sensors. We also discovered that the counter could be used to count many real world events; in different sectors.

TABLE OF CONTENT

Title page i

Certification ii

Dedication iii

Acknowledgement iv

Abstract v

Table of content vi

List of tables ix

List of figures x

CHAPTER ONE

Introduction        1

1.1 Types of circuit 2

1.2 Purpose of design 4

1.3 Scope of the study   5

CHAPTER TWO

    Literature Review 6

2.1 Electron counters 6

2.1.1 Asynchronous (RIPPLE) Counter 8

2.1.2 Synchronous Counter 11

2.1.3 Decade counter 13

2.1.4 Ring Counter 14

2.1.5 Johnson Counter 16

2.2 Computer Science Counters 17

2.3 Web counter 18

2.4 Computer based counters 19

2.5 Mechanical Counters 19

2.6 Microcontrollers                                   21

CHAPTER THREE

Design and construction of a two digit digital counter      24

3.1 Design Work 24

3.1.1 Circuit Description 35

3.1.2 Software Design 36

3.2 Working Principle 39

3.3 Working of the Circuit     41

3.3 The Construction Work 42

CHAPTER FOUR

Tests and Application 45

4.1 Test              45

4.2 Applications 46

CHAPTER FIVE

Discussion, Suggestion For Further Research

And Conclusion 49

5.1 Discussion 49

5.2 Suggestions for Further Research 51

5.3 Conclusion 52

REFERENCES 54