Electronic Devices Presentation

1. AUTO TURNING OUTDOOR
LIGHT
AN AUTOMATED TECHNOLOGY
Roslin Mahmud Joy

2. OVERVIEW
• Goal of the Project
• Circuit Diagram
• Methodology
• Application
• Limitations
• Advantage
• Disadvantage
• Conclusion

3. GOAL OF THE PROJECT
• Automated the light system
• Reduce human effort for controlling circuit
• Reduce power consumption

4. CIRCUIT DIAGRAM

5. METHODOLOGY
• Implement auto turning outdoor light system.
• LDR will be used as light sensors to identify light intensity &
make decision
• BC547 NPN BJT will be used as switch to perform on/off
function
• Two 100k ohm resistor were placed series with the LDR & each
other
• One 1k ohm resistor were placed with series to a LED
• System will turn on the NPN transistor if there is dark

6. APPLICATION
• Automated Street Lights System
• Automated Lights System for Home
• Outdoor Garden Automated Lights System

7. LIMITATIONS
• Require a few a milliseconds or more to respond fully due to
change in light
• Required to pass current & measure voltage to measure
resistance
• Strongly temperature dependent
• Slow due to low response to light

8. ADVANTAGE
• Effortless light turning
• Extend life of lamp
• Economical benefit
• Saving man power

9. DISADVANTAGE
• Light measurement problem;
• Need more time for response;
• Low light problem ;
• Sudden light fall problem;

10. COST
• LDR (5 tk)
• Transistor (2 tk)
• Resistor 3pcs (2 tk)
• Light (2tk)
• Battery (25tk)
• Breadboard (110 tk)
Total cost = 146 tk

11. CONCLUSION
• Reference: https://www.instructables.com/id/How-to-Make-
LDR-Darkness-Sensor-Circuit-Simple-
DIY/?fbclid=IwAR2bwUokgJPeGbiKH5nIlWj4GsSVwDTsZKpcbIHh
aKtAs868QLQw08gDwNI
IS THERE ANY QUESTION?