Description

MAX98357A I2S 3W Class-D Digital Audio Amplifier Module
Product Overview

The MAX98357A I2S Digital Audio Amplifier Module is a compact, high-efficiency Class-D mono audio amplifier designed for microcontrollers and embedded systems with an I2S digital audio interface. It can deliver up to 3.2W output power into a 4Ω speaker at 5V and does not require an external MCLK signal.

The module is an excellent choice for ESP32, Raspberry Pi, Arduino-compatible boards, smart speakers, voice assistants, IoT devices, robotics, and other digital-audio projects.

Key Features
MAX98357A high-quality digital audio amplifier IC
I2S digital audio input
Class-D amplifier with high efficiency
Up to 3.2W output at 4Ω with 5V supply
Supports 8kHz–96kHz sample rates
Supports 16-bit, 24-bit and 32-bit I2S audio
No external MCLK required
Selectable Left, Right, or stereo-to-mono mixing
Five selectable gain levels: 3dB, 6dB, 9dB, 12dB and 15dB
Filterless Class-D operation
Low power consumption
Click-and-pop suppression
Thermal and short-circuit protection
Compact design for embedded applications
Technical Specifications
Parameter Specification
Module IC MAX98357A
Amplifier Type Class-D
Audio Input I2S Digital
Output Mono Speaker
Supply Voltage 2.5V – 5.5V
Recommended Supply 3.3V / 5V
Output Power Up to 3.2W @ 4Ω, 5V
Sample Rate 8kHz – 96kHz
Audio Data 16 / 24 / 32-bit
Gain Options 3 / 6 / 9 / 12 / 15 dB
MCLK Not Required
Channel Selection Left / Right / Mono Mix
Protection Thermal & Short-Circuit
Amplifier Efficiency Up to 92% under specified conditions
Output Filter Filterless operation supported

Specifications are based on the MAX98357A manufacturer’s documentation; actual module-board specifications may vary slightly depending on the module manufacturer.

Pin Description

Typical MAX98357A breakout modules provide:

VIN/VCC – Power supply input
GND – Ground
BCLK – I2S Bit Clock
LRC / LRCLK – I2S Word Select / Left-Right Clock
DIN – I2S Digital Audio Data
SD / GAIN – Shutdown, channel and gain configuration depending on module design
SPK+ / SPK− – Speaker output

Note: Pin names and the exact pin arrangement can vary between MAX98357A module boards.

Applications
ESP32 Audio Projects
Raspberry Pi Audio Systems
Smart Speakers
Voice Assistant Projects
IoT Audio Devices
Digital Audio Players
Robotics
AI Voice Projects
Bluetooth/Wi-Fi Audio Systems
Portable Speaker Projects
Internet Radio
Audio Notification Systems
Embedded Sound Systems
Gaming and Haptic Devices
Compatible Controllers

The module is especially suitable for controllers and computers providing an I2S audio interface, including ESP32 and Raspberry Pi platforms.

Important Note

The MAX98357A is a digital I2S amplifier, so it requires an I2S-compatible digital audio source. It is not a conventional analog-input amplifier. For best performance, use an appropriate speaker impedance and supply voltage within the module’s specifications.kazitechbd.com