Presented by:
ANKITA JAIN
DEEPAK JAIN

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“Design and Development of 89C51 Microcontroller Based Infrared Remote Control system for Audio Amplifier”
Introduction
 It consist of two sections:the receiving section and the transmitting section.
 The receiving section consists of an Infrared remote.
 In this project I’m using a Sony Infrared remote.
 Whenever a key is pressed on the remote a coded pulse train is emitted. The pattern of the pulse train depends on the key pressed.
 The transmitting section consists of the 89c2051 microcontroller.
 The microcontroller is programmed so as to decode the incoming coded pulse train which is sensed by an infrared sensor (TSOP1238).
 Once the coded pulse train is received it is decoded to recognize the corresponding amplifier for which the key is pressed and the necessary action is taken.
 The analog multiplexer then select the corresponding keys for increasing or decreasing the volume of audio amplifier.
Block Diagram
Circuit Diagram
• TSOP
 TSOP12.. is the standard IR remote control receiver series, supporting all major transmission codes
Pin Configuration
• Pin 1: ground
• Pin 2: output
• Pin 3: supply voltage
 Photo detector and preamplifier in one package
 TTL and CMOS compatibili
Output active low
 Low power consumption
 Lead (Pb)-free component
 Improved immunity against ambient light
Output of DSO
Digital potentiometer
 A digital potentiometer is a digitally-controlled electronic component that mimics the analog functions of a potentiometer.
 . It is either built using an R-2R integrated circuit or a Digital-to-analog converter.
 A digital potentiometer is an electronic component that is often controlled by digital protocols like I²C and SPI, as well as more basic Up/Down protocols.
 Some typical uses of digital potentiometers are in circuits requiring gain control of amplifiers (frequently instrumentation amplifiers), small-signal audio-balancing, and offset adjustment.
 Some Digipots come with non-volatile memory, so that they retain their last programmed position after they have been power cycled. Most, though, are volatile, i.e. after they are power cycled they will default to a standard value, which is usually the mid-point.
HARDWARE DEVELOPMENT
 89c2051 microcontrolle
 Infrared remote
 Infrared sensor (TSOP1238)
 MAX 232
 Resistances: 3x 4.7K
 Capacitances: 2x 22pf, 1x 220uf
 Crystal Oscillator
FOR 5V POWER SUPPLY CIRCUIT
 12-0-12 transformer
 2 X 1N4007 (diodes)
 2 X 1000uf capacitances
 LM7805 voltage regulator
SOFTWARE DEVELOPMENT
Requirements:
 Any operating system supporting web browsing like Windows 95, 98, 2000, XP, NT, Linux etc.
 Visual basics – for coding and developing.
 Web browsers like internet explorer, Mozilla firefox , opera etc.

thnq for information.