These are switching or PWM (Pulse Width Modulation) amplifiers. The transistors switch rapidly between fully ON and fully OFF states. They boast massive efficiency (90%+), making them perfect for portable, battery-powered devices.
). High DC voltage will instantly destroy your speaker's voice coil.
"LM386 audio amplifier circuit project PDF" → Look for "LM386 datasheet" (National Semiconductor) – it contains a practical project on page 6. practical audio amplifier circuit projectspdf
Amplify a 10mV–100mV input (microphone or magnetic pickup) to ~1V peak-to-peak.
Typical components include transistors (BJTs or MOSFETs) or integrated amplifier ICs, coupling and bypass capacitors, resistors for bias and feedback networks, heat sinks for power devices, and power supplies (regulated linear supplies for low noise or switching supplies for compactness). Protection elements such as current limiting, thermal shutdown, and speaker relays protect both the amplifier and connected speakers. These are switching or PWM (Pulse Width Modulation)
2x 220µF (Power smoothing), 2x 0.1µF (Input coupling) Designing the Virtual Ground
Logarithmic (Audio) taper resistors used for smooth, human-ear-friendly volume control. 3. Project 1: The Ultra-Simple LM386 Mini-Amp (Low Power) Amplify a 10mV–100mV input (microphone or magnetic pickup)
: Using transistors in the active region to increase signal strength.
Discharges large power supply capacitors before touching them. 2. Project 1: The LM386 Low-Voltage Mini Amplifier