Main Features

Amplifier IC: PAM8403
Amplifier class: Class-D
Audio channels: 2-channel stereo
Output: Up to approximately 3 W + 3 W
Supply voltage: Typically 5 V DC
Low standby/current consumption
High efficiency compared with traditional Class-AB amplifiers
Compact and lightweight PCB
Left and right independent audio channels
Designed for direct connection to small speakers
Usually operates without a large heatsink because of its high efficiency

How the PAM8403 Works

The board accepts a small audio signal through its L (Left) and R (Right) input channels. The PAM8403 IC processes and amplifies these signals using a switching output stage.

Unlike a traditional Class-AB amplifier, a Class-D amplifier rapidly switches its output transistors between states. This significantly reduces power dissipation and allows a small PCB to deliver relatively high audio power.

The amplified signal is then connected to the speakers through the L+ / L− and R+ / R− outputs.

Typical signal path

Audio source → PAM8403 input → Class-D amplification → Left/Right speakers

Power Supply

The PAM8403 is intended for low-voltage DC power, commonly around 5 V.

A suitable power source can include:

USB 5 V
Power bank
5 V regulated adapter
5 V battery supply through an appropriate regulator
Arduino/ESP32 project power supply, provided sufficient current is available

Do not connect 12 V directly to a standard PAM8403 module. Doing so can damage the amplifier IC.

Speaker Connection

The module provides two independent channels:

L+ / L− → Left speaker
R+ / R− → Right speaker
Audio Quality

The PAM8403 can provide good sound quality for its size and power level. It is suitable for:

Music

Voice

Podcasts

Notifications

Alarm sounds

Electronic project audio

Main Features

How the PAM8403 Works

Typical signal path

Power Supply

Speaker Connection

Audio Quality

PAM8403 Module Digital Amplifier Board 2x3w D Class Board