The 5W Audio Power Amplifier designed by using LM384 From Texas Instruments. This IC available in two packages 8 pin and 14 pin. It is basically a high voltage power supply this circuit operates with 22 Volt supply. this circuit build around IC LM384, potentiometer P1, and four capacitor, loud speaker and few other components.
LM384 5W Audio Power Amplifier Circuit gives voltage gain upto 50 and provides high input Impedance 150KΩ. 12V Regulated DC power supply applied as bias to this circuit, LM384 Configured in Inverting mode of operation hence it will acts as a typical audio amplifier circuit. If your design has pre-amplifier and Audio Volume control then you can directly feed audio signal to the Inverting pin 6 of LM384.
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Construction and Working
Here the variable voltage divider on input signal for volume control potentiometer is connected to the inverting terminal of IC. C1 capacitor is connect to power supply bypass is shunted to ground. C2 capacitor connect to pin 1. C3 capacitor connect together with R2 resistor creates low-pass output filter prevents very high frequency from going to speaker. C4 capacitor is connect to output of IC and input to speaker.
The C1 bloking capacitor prevents DC from going to the speaker. R1 resistor connect together with C3 creates a low-pass output filter prevents very high frequencies from going to speaker. Input stage of LM384 allows ground referenced input signal hence its easy to put level controller, one half of the supply voltage delivered at the output pin so we can choose supply voltage depends on required output voltage.
LM384 suitable for long duration operation and also the package contains copper lead frame comprising a heat sink. Short circuit proof with internal thermal limiting makes this IC suitable for low resistance load. This IC supports single and two layer PCB without any special modifications.