How to make 20w Audio Amplifier
20w amplifier using ic TDA7240
The TDA7240A is a 20W bridge audio amplifier IC . COMPACT HEPTAWATT PACKAGE in 7 pin packing. The audio amplifier shown here is based on the TDA7240 IC . The ic TDA 7240 is an audio amplifier IC that can deliver 20 watts of audio output power into a 4 ohm load. The circuit of audio amplifier using tda7240 IC requires minimum external parts.
The IC also has a lot of good features like loud speaker protection, short circuit protection low noise, thermal shut down, low distortion/low noise, high current capability etc. This 20w Audio Amplifier circuit can be operated from a 12V DC to 18V single power supply, and this makes it very useful in car audio applications. This circuit is very compact size and uses very less component. Led is used as indicator which indicates on or off the supply.
• In this circuit there is no any audio /mp3 reader but it works on with audio input signal which is produced from any reader or player. Input provided is redymade from any audio player like mp3 player or mobile phone or other devices in this project, Because this ic is not able to decoding the signal into audio form , this is only works on predefined signal to make it Amplified at required level.
• Any audio input signal is given on pin no 3 of ic which is passes through a capacitor. Carefully connect the audio input with this circuit, one terminal is ground in audio output from player and this should connected with circuit ground and other non-ground terminal of audio player connect with ic (pin 3). Pin 5 and 7 is the output which is connected with speaker. Pin 4 is grounded and pin 6 is supply input.
A switch may be used between ground pin 2 for the circuit to remain in Standby mode
• You can use two ic for making two circuit for seperate two channel input and output for stereo mode and get stereo output 20w-20w at both output. Use suitable heatsink with for protection from heat.
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