In this tutorial, we are going to make an “Acoustic Audio Amplifier Circuit” using LM386. We all know that amplifiers hold great prominence in the scope of the electrical and electronics industries. Here we design a simple audio amplifier by using LM386, it is a low-voltage power amplifier used exclusively in the minimal voltage required consumer applications. It is a mini 8-pin DIP package with having body size of 9.60mm×6.35mm.
Initially, the gain of the device is maintained at 20, but adding external components such as capacitors and resistors in between 1 and 8 pins will enhance the gain values from 20 to 200. Here LM386 acoustic audio amplifier circuit is designed with Gain and Bass control. IC LM386 comes in different packages, and amplifier modules are available with different specifications, but the following circuit contains additional features to control gain & bass.
Hardware Required
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | IC | LM386 | 1 |
| 2. | Variable Resistor | 10KΩ | 3 |
| 3. | Audio Input Jack | – | 1 |
| 4. | Resistor | 1KΩ,10KΩ | 1,2 |
| 5. | Capacitor | 10uf,0.1uf,0.01uf,100uf/25V | 2,1,1,1 |
| 6. | Speaker | – | 1 |
| 7. | LED | – | 1 |
| 8. | Connecting Wires | – | – |
| 9. | Battery | 12V | 1 |
Circuit Diagram
LM386 Pin Configuration
LM386 Audio Amplifier Module
This is SMD (surface mount device) based LM386 audio amplifier module. It has a volume control trimpot, 200x fixed gain, 1 Channel, 325mW power, and needs 4-12V for operation. The LM386 audio amplifier module is handy for providing basic audio amplification in a project.
Working Explanation
LM386 IC is the main part of the circuit. Here we need to put a variable resistor or trimpot with a few passive components, for variable volume, gain, and bass. Now input audio is given to the non-inverting pin of LM386 and inverting pin is grounded. Vcc supply can be given from +5V to +12V and the output automatically biases to one-half the supply voltage. And gain control variable resistor is placed between gain pins 1 & 8 of lm386, then the bass control variable resistor is connected between the output and pin 1 of LM386. Where n/c open is no contact open terminals. LED1 represents the power supply presence to the LM386 acoustic audio amplifier circuit.
Application
- It can be used in Radio amplifiers.
- Portable music players can also use this circuit.
- In audio booster circuits, etc.
