Practical Audio Amplifier Circuit Projectspdf 'link' -

The audio input is fed through the potentiometer to the non-inverting input of the LM386 (pin 3). A 10µF capacitor between pins 1 and 8 sets the gain to 200. The output is taken from pin 5 through a 1000µF capacitor to the speaker, which blocks DC and protects the speaker from damage. A 220µF capacitor across the power supply provides filtering and stability.

Move the circuit away from fluorescent lights or mains power strips. practical audio amplifier circuit projectspdf

Connect a series network of a 0.05 µF capacitor (C4) and a 10 Ω resistor (R2) from Pin 5 to ground. This prevents high-frequency oscillations that can destroy the chip. The audio input is fed through the potentiometer

+45V │ ┴ 10000µF │ ├──IRF9540 (P-channel) Source │ │ │ Gate─┬─100Ω─┬──From VAS stage │ │ │ │ Drain──┐ 100kΩ │ │ │ │ │ ┴ GND │ │ ├──Output Node─────Speaker (+) │ │ │ Source of IRF540 (N-channel) │ │ │ Gate─┬─100Ω─┬──From VAS stage │ │ │ │ Drain─┐ 100kΩ │ │ │ -45V │ ┴ GND │ │ ┴ 10000µF │ GND A 220µF capacitor across the power supply provides

: Versatile integrated circuits used as the foundation for many DIY preamp and headphone projects. Why Build Your Own?