BLUETOOTH CONTROLLED HIGH POWER AUDIO AMPLIFIER

1. BLUETOOTH CONTROLLED HIGH
POWER AUDIO AMPLIFIER
Presented By:
Bijay Raj Paudel (Roll No: 067/BEX/105)
Sagar Mali (Roll No: 067/BEX/133)
Sujan Shrestha (Roll No: 067/BEX/140)

2. Decent quality High Power Audio Amplifier
8051 Microcontroller based
Digital control over tone, effects & volume
Wireless Bluetooth Interface
Control via Computer Software and/or Keypad
INTRODUCTION

3. To construct cost effective audio amplifier.
To implement 8051 μc along with it’s interfacing.
To control the system via wireless Bluetooth module.
To program μc & develop GUI based PC application.
To improve our programming & practical skills.
OBJECTIVES

4. PROBLEM STATEMENTS
& SOLUTIONS
Present Amplifier
Analog Control
Wired
Less Portable
No Display
Our Amplifier
Digital Control
Wireless
More Portable
LCD Display

5. METHODOLOGY
System is divided into two major parts :
 Main Board
 Remote and PC Interface

6. Main Board
Audio
Input

7. Remote & PC Interface

8. Pre Amplifier
 Optimizes signal
 Reduces noise & disturbances
 Includes multi Op-Amp stages and transistorized
stages for low level signal amplification and filter
Brief Description of Main
components

9. Power Amplifier
 100 watt max class AB audio amplifier
 Adjustable output transistor biasing to avoid
crossover distortion
 Overheat protection and short circuit output
protection
Brief Description of Main
components

10. Digital Potentiometers
• A digital potentiometer (informally a digipot) is a
digitally controlled electronic component that mimics
the analog functions of a potentiometer.
• It is used for trimming and scaling analog signals by
microcontrollers.
Brief Description of Main
components

11. 8051 Microcontroller (AT89s52, AT89s2051)
 256x 8-Bit Internal RAM
 In-System Programmable (ISP) Flash Program Memory
– Serial Interface for Program Downloading
 32 Programmable I/O Lines in s52 and 16 in s2051
 Fully Static Operation: 0 Hz to 24 MHz
 Programmable Serial UART Channel
 Low Power Idle and Power Down Modes
Brief Description of Main
components

12. EEPROM
 Holds the data even when the power is removed
 Used to save previous digital settings
 Can also be programmed to hold custom
greeting messages
Brief Description of Main
components

13. Bluetooth Module
 Heart of the wireless data communication
 Two TX and RX modules to be used
 Transfers data to & from μc using UART protocol
Brief Description of Main
components

14. MAX 232 IC (TTL to RS232 Convertor)
• Microcontroller logic levels 0-0.5 V and 4.5-5 V
• Max 232 circuit converts signal from RS-232 to 5 V TTL
signal level
• IC 7805 to provide power supply to MAX 232
Brief Description of Main
components

15. Brief Description of Main
components
RS232 to USB Convertor
 Converts RS232 to USB signal
 Makes the system more portable

16. Brief Description of Main
components
LCD
 Graphical LCD is planned to be used if available
instead of normal alphanumeric LCD.
 Ability to display custom sized fonts,
images and audio spectrum visualization
instead of just characters.

17. PC and GUI Control Application
 Runs on OS of PC
 Based on C# .NET
 To change amplifier setting
Brief Description of Main
components

18. Auditorium Hall
 Seminar
 Presentation
 Lecture
Theatrical and Concert sound reinforcement
Home Theater System
Car Audio System
Guitar Amplification
APPLICATIONS

19. S.N. Item Unit Cost(Rs.) Quantity Total (Rs.)
1. Power Transistor 60 6 360
2. Microcontroller 150 4 600
3. EEPROM 200 1 200
4. Speaker (100 Watt) 1000 2 2,000
5. Bluetooth Module 1500 1 1,500
6. Digital Potentiometer 200 8 1,600
7. Audio Op-Amp 100 5 500
8. PCB Board 800 1 800
9. RS232 to USB
convertor
1000 1 1,000
10. Others ~ ~ ~2,500
Grand Total ~11,000
COST ESTIMATION

20. TIME ESTIMATION
S.N. Title Estimated Time
1. Project Identification 1 week
2. System Planning 1 week
3. System Analysis 1 week
4. System Design 2 weeks
5. System Implementation 3 weeks
6. Troubleshooting 1 week
Total 9 weeks

21. CONCLUSION
Thus, our final product is going to be HIGH POWER AUDIO
AMPLIFIER.
We expect to build BLUETOOTH INTERFACE between system &
digital control.
Finally, it will have it’s own GUI BASED CONTROL APPLICATION
which can be operated through Bluetooth enabled devices.

22. BOOKS:
A.S. Sedra and K.C. Smith, “Microelectronics Circuits Theory and
Application”, 5th edition, Oxford University Press
Muhammad Ali Mazidi, “8051 Microcontroller and Embedded Systems”,
Prentice Hall, 2006
Douglas Self, “Audio Power Amplifier. Design Handbook”, 3rdedition.
WEBSITES:
http://hackaday.com/2011/06/27/stereo-amplifier-with-digital-volume-
control/
http://www.diyaudio.com/forums/solid-state/
http://en.wikipedia.org/wiki/Bluetooth
http://www.bluetooth.com/
REFERENCES

23. THANK YOU !