The document outlines a project on an alcohol interlock device that estimates blood alcohol content from breath samples using an MQ-3 alcohol sensor. It emphasizes the need for such a system due to high road accident rates caused by drunk driving, detailing its components and applications in transportation safety. The conclusion highlights the potential of this technology to significantly reduce drunk driving incidents.

1. Alcohol Interlock
(8th Sem Major Project)
Submitted To: Submitted By:
Mr. Yogesh Kumar(HOD) Prateek (13EMCEE061)
EE Dept. Puneet (13EMCEE064)
Rajat(13EMCEE067)

2. Content
 Introduction
 Need of alcohol interlock
 Parts of alcohol interlock
 Microcontroller
 Circuit diagram
 Block diagram
 Flow chart
 Application
 Conclusion

3. INTRODUCTION
It is a device for estimating blood alcohol content
(BAC) from a breath sample. In simple terms it is a
device to test weather a person is drunk or not.
Our breathalyzer uses the MQ-3 alcohol sensor or
mq3 module .It is a simple and fun to do project.

4. Introduction
 It is a device for
estimating blood
alcohol content (BAC)
from a breath sample.
In simple terms it is a
device to test weather
a person is drunk or
not.
 Our breathalyzer uses
the MQ-3 alcohol
sensor or mq3
module .It is a simple
and fun to do project

5. Need of Alcohol interlock
 According to TOI survey 34% of
the accidental deaths take place on
the road because of the reckless
driving of the driver after
consumption of the alcohol.
Furthermore, the leniency of the
law enforcers increased the rate to
42% in the following year.
Keeping in mind the substandard
condition of the Indian roads and
the accidental death rate due to
alcohol consumption, a system
needed to be designed which fails
the attempt of the driver to initiate
the engine. The system designed is
used as alcohol interlock or
breathanalyzer

6. Parts of alcohol interlock
 Mq3 module
 At mega 328 microcontroller
 LCD 16*2
 Crystal 16 MHz
 Buzzer 6V
 Led
 Regulated IC 7805
 12V adopter
 Some resistor and capacitor
 Pcb board
 Transistor
 Diode

7. MQ-3 Alcohol Ethanol Gas Sensor
Module
 Gas leakage monitoring device can be used in
homes and factories, and is suitable for the
detection of alcohol;
 Sensitivity adjustable the blue digital
potentiometer adjustment (Figure)
 Before the use of the operating voltage 5V
power supply at least warm-up for more than
two minutes, the sensor slightly hot is normal;

8. Fig.-MQ3 Sensor
 Output in the form
 analog voltage output
 digital switching outputs
(0 and 1)
 With fixed bolt hole for
easy installation
 Small board PCB size:
4.5cm * 1.8cm

9. LCD 16*2 interfacing with 328

10. POWER SUPPLY
1.Unregulated Linear Power Supply:
 Unregulated power supplies contain four basic
components: transformer, rectifier, filter capacitor, and a
bleeder resistor.
 The ripple can be reduced by changing the filter
capacitor to an LC (inductor-capacitor).

11. 2.Regulated Linear Supply:
 A regulated linear power supply is Identical to the
unregulated linear power supply except that a 3-
terminal regulator is used in place of the bleeder
resistor.
 The output voltage has negligible ripple, very small
load regulation, and high reliability.

12. Microcontroller
ATMEGA 328 microcontroller:-
Basic diagram-

13. Pin Diagram

14. Circuit diagram

15. Block diagram

16. OVERALL FLOWCHART

17. Application
 It can used by traffic police to check the drivers
of vehicles weather they are drunk or not.
 This instrument is able to reserve its place in
the government offices, especially in the
service sectors like railways, aviation, and in
roadways.

18. CONCLUSION
CONCLUSION
 The technology can immensely decrease the
rate of drunken driving cases which often
leads to accidental deaths. By capitalizing on
recent technological advancements that will
not let the car to be driven if the driver has
drunk the alcohol.

19. Thank you