1. VEHICLE DENSITY CONROLLED AUTOMATIC TRAFFIC LIGHT
BTECH 2014 i Dept. Of EEE, KMPCE
TABLE OF CONTENTS
Chapter No. Title Page No.
List of figures ii
List of table iii
List of Abbreviations iv
1. INTRODUCTION 1
2. THE POWER STAGE 4
2.1 Power Supply 4
2.2 Selection of Components 4
3. THE CONTROL STAGE 11
3.1 The8051 Microcontroller-AT89S51 11
4. SENSORS 17
5. FLOW CHART AND CIRCUIT DIAGRAM 19
6. RESULTS AND CONCLUSION 25
REFERENCES AND LINKS 26
APPENDIX 1 27
APPENDIX 2 28

2. VEHICLE DENSITY CONROLLED AUTOMATIC TRAFFIC LIGHT
BTECH 2014 ii Dept. Of EEE, KMPCE
LIST OF FIGURES
Figure No. Title Page No.
2.1 Transformer 4
2.2 Bridge Rectifier 6
2.3 Regulator IC 7
2.4 Full Wave Rectifier with Capacitor Filter 7
2.5 Capacitor 9
2.6 Led 10
3.1 Pin Diagram 13
4.1 Object Sensor 17
4.2 IR Diodes 17
4.3 Circuit for Sensor 18
5.1 Circuit Diagram 22
5.2 Block Diagram 23
5.3 Sensor Circuits 24

3. VEHICLE DENSITY CONROLLED AUTOMATIC TRAFFIC LIGHT
BTECH 2014 iii Dept. Of EEE, KMPCE
LIST OF TABLES
Sl No. Name Page No.
3.1 Port alternate functions 14
3.2 Port 3 alternate functions 15

4. VEHICLE DENSITY CONROLLED AUTOMATIC TRAFFIC LIGHT
BTECH 2014 iv Dept. Of EEE, KMPCE
List of Abbreviations
Vcc - Power supply
GND - Ground
Vs - SecondaryVoltage
Vp - Primary Voltage
Ns - SecondaryTurns
Np - Primary turns