The MAX98357 Audio Decoder Module is a compact digital audio amplifier designed to convert I²S digital audio signals directly into high-quality amplified sound. It integrates a DAC and Class-D amplifier in a single chip, eliminating the need for an external DAC. This module is widely used with ESP32, Raspberry Pi, and other microcontrollers for audio playback, voice alerts, IoT sound output, and embedded multimedia projects.
Core Module Specifications
• Module Type: Digital audio decoder with amplifier
• IC Used: MAX98357A
• Audio Input Type: I²S digital audio
• Output Type: Amplified mono audio
Electrical & Interface
• Operating Voltage: 3.0 V – 5.5 V
• Logic Level: 3.3 V compatible
• Audio Interface Pins: BCLK, LRC (WS), DIN
• Control Pins: SD (shutdown), GAIN (variant dependent)
• Speaker Output: Differential (SPK+ / SPK−)
Performance Characteristics
• Clear and low-noise audio output
• High efficiency Class-D amplification
• No external DAC required
• Suitable for voice and music playback
Physical Characteristics
• Module Type: PCB-mounted audio module
• Form Factor: Compact and lightweight
• Onboard Components: Audio IC and passive parts
• Easy integration into small enclosures
Compatibility
• ESP32 (I²S audio output)
• Raspberry Pi
• Arduino (with I²S support)
• STM32 and other I²S-capable MCUs
• IoT and embedded audio systems
Key Advantages
• Direct I²S to speaker solution
• High efficiency with low heat
• Minimal external components required
• Excellent for digital audio projects
Technical Insights
• Supports left, right, or mixed mono audio
• Gain configuration via pin or resistor
• Requires correct I²S clock configuration
• Not suitable for analog audio input
Applications
• Voice alerts and notifications
• Smart assistants and IoT devices
• Embedded audio playback
• Talking robots and machines
• DIY digital audio projects
Pro Tip
• Match I²S sample rate correctly in firmware
• Use short speaker wires to reduce noise
• Provide clean power for best audio quality
• Use shutdown pin to save power when idle
Package Includes
• 1 × MAX98357 Audio Decoder Module