LM386 audio amplifier stereo circuit diagram

stereo audio amplifier lm386 PCB 3D board

LM386 audio amplifier stereo circuit diagram and PCB. This is an audio amplifier with 2 LM386 integrated circuits. Basically, it deals with the use of 2 amplifiers, as in another article posted at a time ago. But this time it includes a printed circuit board for stereo version, in addition to power supply. The circuit operates with power supply or batteries of 6 to 12 volts. The best performance will be when using a 12V power supply and 8 Ohms speakers.

The operation of the circuit is simple and based on the LM386, responsible for the amplification, the stereo audio signal is coupled by the capacitors C5 and C11, the stereo potentiometer P1, is used to adjust the volume.

The components attached to pins 1 and 8 control the gain:

  • No component: Gain = 20.
  • 10μF Capacitor (Jumper on R2 and R4): Gain = 200
  • 10μF Capacitor and 1.5K Resistor: Gain = 50

The output is coupled via 470μF Capacitor, if you want to use with headphones add resistors from 100 to 220 Ohms to 1Watt in series with the output.

The LM386M-1 and LM386MX-1 are power amplifiers designed for use in low voltage consumer applications. The gain is internally set to 20 to keep external part count low, but the addition of an external resistor and capacitor between pins 1 and 8 will increase the gain to any value from 20 to 200.

The inputs are ground referenced while the output automatically biases to one-half the supply voltage. The quiescent power drain is only 24 mW when operating from a 6-V supply, making the LM386M-1 and LM386MX-1 ideal for battery operation.

  • Battery Operation
  • Minimum External Parts
  • Wide Supply Voltage Range: 4 V–12 V or 5 V–18 V
  • Low Quiescent Current Drain: 4 mA
  • Voltage Gains from 20 to 200
  • Ground-Referenced Input
  • Self-Centering Output Quiescent Voltage
  • Low Distortion: 0.2% (AV = 20, VS = 6 V, RL = 8 Ω, PO = 125 mW, f = 1 kHz)
  • Available in 8-Pin MSOP Package

Some names found for this IC – LM386 audio amplifier stereo circuit diagram

Código Maximum voltage in VDC Maximum power in mW Package
LM386N-1 LM386N-2 LM386N-3 15 700 PDIP (8)
LM386N-4 22 1000 PDIP (8
LM386N 15 700 PDIP (8
LM386M 15 325 SOIC (8)
LM386MM-1 15 325 SOIC (8)
M386MX-1 15 325 SOIC (8)
LM386MMX-1 15 325 VSSOP (8)

Schematic of the audio amplifier LM 386 stereo

Stereo Audio Amplifier Lm386 Schematic

Printed Circuit Board PCB for mounting the LM386N audio amplifier stereo circuit diagram

Printed Circuit Board Pcb For Mounting The Lm386N Audio Amplifier Stereo Circuit Diagram
Printed Circuit Board Pcb Component View, For Mounting The Lm386N Audio Amplifier Stereo Circuit Diagram
Printed Circuit Board Pcb Component Silk, For Mounting The Lm386N Audio Amplifier Stereo Circuit Diagram

BOM for assembly lm386 stereo audio amplifier

Part Value
Resistors 1/4 Watt 5%
R1 560 – Green, Blue, Brown, Gold
R2, R4 1K – Brown, Black, Red, Gold
R3, R5 10 – Brown, Black, Black, Gold
P1 10K – Double Potentiometer
C1 2200µF/ 16V — Polarized Electrolytic Capacitor
C2, C8, C14 100nF — 100n, 104, .1, 0.1 — Ceramic or Polyester Capacitor
C3, C9 100µF/ 16V — Polarized Electrolytic Capacitor
C4, C10 10µF/16V — Polarized Electrolytic Capacitor
C5, C11 4.7µF/16V — Polarized Electrolytic Capacitor
C6, C12 470µF/16V — Polarized Electrolytic Capacitor
C7, C13 47nF – 473, 47n, 0.047 – Ceramic or Polyester Capacitor
D1, D2, D3, D4 1N4004 or equivalent – Semiconductor diode
IC1, IC2 LM386N – Audio amplifier integrated circuit
LED1 Led Vermelho 5 mm
Connectors and their functions
CN1 (AC) Terminal block 2 pin 5.08 mm — Connector to connect the transformer.
CN2 (IN) 3-pin 2.54 mm connector JST-XH-03 – Audio input connector
CN3 (OUT) Terminal block 2 pin 5.08 mm – Audio Output Connector
TR1 6 to 9 Volts/ 500mA Transformer
Solder, Wires, PCB, Box, Knob potentiometer, etc.

Download PDF files for assembling the stereo amplifier with LM386: LM386 Datasheet, PCB, Schematic, Component Layout and Silk Screen

Gerber Added

How useful was this post?

Click on a star to rate it!

Average rating 4.4 / 5. Vote count: 7

No votes so far! Be the first to rate this post.

About the author
Xtronic.org blog author. Electronics technician for the technical school of Brasilia - Brazil. Interested in electronics, circuits and technology in general.

13 thoughts on “LM386 audio amplifier stereo circuit diagram”

  1. Hi Toni, this circuit is exactly what what I’ve been searching for, small and simple. Unfortunately I cannot link to download the actual size PCB foil layout (Not Found Error 404). Is there any way to get that download? Any assistance from you or anyone who might be reading this would be greatly appreciated.
    Much thanks.

  2. pregunto otra ves que tipo de transformador es, porque no se consigue de 9.6 volt, si no de 6 o 9 volt y si es encapsulado saludos desde venezuela


Leave a Comment

Exit mobile version