Designing an Op-Amp Based Fire Alarm Circuit.pptx

This slide describes the design and simulation of a fire alarm circuit using an LM358 operational amplifier (op-amp). The circuit utilizes a 10k NTC thermistor to detect temperature changes, triggering a buzzer and LED when the temperature exceeds a preset threshold. The slide details the circuit's working principle, component selection, simulation results, and PCB layout.

1. Partho Prosad Page 1 /18 Presented by: Partho Prosad (2022371) Department of Electrical & Electronic Engineering INDEPENDENT UNIVERSITY, BANGLADESH EEE222L PROJECT PRESENTATION Designing an Op-Amp Based Fire Alarm Circuit Course Instructor: Md. Iftadul Islam Sakib

2. Partho Prosad Page 2 /18 Motivation and Background Objective Proposed System, Circuit Diagram and Component List Simulation and PCB design Analysis and Calculation Limitation Conclusion and Future Scope Outline

3. Partho Prosad Page 3 /18 Motivation and Background Fire safety is a critical concern for both residential and commercial properties. Early detection of fires can help prevent property damage, injuries, and loss of life. An op-amp based fire alarm circuit can provide a reliable and cost-effective solution for detecting fires. Op-amps are widely available and easy to integrate into electronic circuits. The circuit can be designed to detect changes in temperature or smoke, or both.

4. Partho Prosad Page 4 /18 Motivation and Background ( Contd …) By using an op-amp based circuit, false alarms can be minimized, reducing the risk of unnecessary evacuations. The circuit is a flexible solution since it can be altered to fit various settings and applications. Building and testing an op-amp-based fire alarm circuit may be a fun and informative activity for both electronics enthusiasts and students. It can aid in the development of practical skills in circuit design, testing, and troubleshooting.

5. Partho Prosad Page 5 /18 Objective My first objective in this project is to save mankind from fire. My second objective in this project is to prevent false alarms. Design and build an op-amp based fire alarm circuit that can detect changes in temperature or smoke, or both. Optimize the circuit to suit different environments and applications. Share project results through technical reports, presentations, and online platforms, thereby contributing to the understanding and development of fire alarm systems.

6. Partho Prosad Page 6 /18 Proposed System This fire alarm circuit will be based on op-amp amplification worked as a comparator mode. This circuit will be designed to detect changes in temperature and/or smoke using NTC Thermistor. This circuit will be powered by a reliable and efficient power source, such as a battery or DC power supply. This circuit will include user-friendly features such as a test button and LED indicators for system status. The circuit will be optimized for low power consumption.

7. Partho Prosad Page 7 /18 Component List One LM358 Op-Amp (Two Output) One 10K Resistor One 10K NTC Thermistor One Potentiometer (POT) or Variable Resistor One 5V Buzzer. One Blue-LED Some Voltmeter, Wire and Ground.

8. Partho Prosad Page 8 /18 Circuit Diagram Op-Amp Based Fire Alarm Circuit

9. Partho Prosad Page 9 /18 Simulation (Video)

10. Partho Prosad Page 10 /18 PCB Design Figure : PCB Layout . Figure 3 : PCB Layout Upper Part (3D).

11. Partho Prosad Page 11 /18 PCB Design ( Contd …) Figure : PCB Layout Front Part (3D) Figure : PCB Layout Back Part (3D)

12. Partho Prosad Page 12 /18 Analysis and Calculation

13. Partho Prosad Page 13 /18 Limitation The fire alarm circuit is limited to detecting temperature and smoke changes and may not detect other types of fires, such as those caused by electrical faults The circuit's accuracy may be affected by factors such as humidity, wind, and air flow, which may cause false alarms or missed detections The circuit may require regular maintenance and testing to ensure its reliability and effectiveness, which may increase its overall cost and complexity The circuit's sensitivity may need to be adjusted to suit different environments and applications, which may require additional calibration and testing Overheating can damage the circuit

14. Partho Prosad Page 14 /18 Conclusion and Future Scope Bangladesh, one of the densestly inhabited nations, frequently experiences life-threatening fire mishaps that also seriously harm property. This project demonstrates how to use an op-amp and its operating principle to create a straightforward and reasonably priced fire alarm circuit. The hardware prototype needed to understand op-amp comparator mode, and simulation was used to validate the findings. Anyone can replicate this module and prevent a fire mishap at home using the project's inexpensive and widely available components: an op-amp, a fixed resistor, a thermistor, and a potentiometer. This project can still be improved further by adding new features to get over the project's restrictions.

15. Partho Prosad Page 15 /18 Contribution of The Team Members Partho Prosad Student of EEE Dept. at IUB. ID: 2022371 Tazrian Noor Abhash Student of EEE Dept. at IUB S pecial thanks to my friend :

16. Partho Prosad Page 16 /18 References [1] Nasir, Syed. "Introduction To LM358 - The Engineering Projects". The Engineering Projects, 2017, https://www.theengineeringprojects.com/2017/07/introduction-to-lm358.html . [2] "Heat Detector - Wikipedia". En.Wikipedia.Org , 2021, https://en.wikipedia.org/wiki/Heat_detector#:~:text=Fixed%20temperature%20heat%20detectors,-This%20is%20the&text=The%20most%20common%20fixed%20temperature,C%20(136.4%C2%B0F) [3] "Comparators". Tutorialspoint.Com , 2021, https://www.tutorialspoint.com/linear_integrated_circuits_applications/linear_integrated_circuits_applications_comparators.htm . [4] “Thermistor Output Table”. Bapihvac.Com , 2021, https://www.bapihvac.com/wp-content/uploads/2010/11/Thermistor_10K-2.pdf . [5] “Types of Fires for Heat Detection”. Covesmart.Com , 2021, https://www.covesmart.com/blog/how-a-heat-detectors-works/ .

17. Partho Prosad Page 17 /18 Appendix Thermistor temperature versus resistance table LM358 - pin diagram Potentiometer pin diagram

18. Partho Prosad Page 18 /18 Any questions, comments or suggestions? Email :  [email protected]