MAX98357A I2S Audio Amplifier Module 3.2W Class D Output with Selectable Gain for Embedded Projects

MAX98357A I2S Input Audio Amplifier Board 3W Class D Overview A compact Class D amplifier module based on the MAX98357A audio decoder. Designed for embedded audio projects, the module accepts I2S digital input and delivers up to 3.2W into 4 ohm speakers while running efficiently from lowvoltage supplies. Key benefits Small, efficient Class D amplification for battery and portable projects. Low power draw and efficiency reduce heat and extend runtime. Direct I2S input for clean digital audio transfer from microcontrollers and digital audio sources. Avoids extra DAC hardware. Selectable fixed gain from 3 dB to 15 dB, with a default of 9 dB, allowing easy matching to speaker sensitivity and source levels. Builtin heat and overcurrent protection for safer operation in embedded systems. Features Model: MAX98357A Output power: 3.2 W into 4 ohm, 1.8 W into 8 ohm (with 5 V supply) Supply range: 2.7 V to 5.5 V Audio input: I2S digital audio compatible with 3.3 V or 5 V logic levels Sample rate support: 8 kHz to 96 kHz PSRR: 77 dB typical at 1 kHz (I2S) Selectable gain: 3 dB, 6 dB, 9 dB, 12 dB, 15 dB (default 9 dB). Set gain by applying pullup or pulldown resistors or wiring the gain select pin. Protections: thermal and overcurrent protection integrated Size: approximately 1.9 x 1.8 cm Compatibility and integration I2S input is intended for digital audio streams from microcontrollers, DSPs, and single board computers that output I2S. Note that I2S is a digital audio protocol and not the same as I2C. Logic level tolerant to common 3.3 V and 5 V systems, simplifying integration with development boards. What is included 1 set MAX98357A audio amplifier module Practical considerations Soldering is required if you need to add connectors to the module. Allow 0 to 2 mm tolerance for manual measurements. Product appearance may vary slightly due to lighting during photography. Typical applications Portable speakers and batterypowered audio devices where efficiency and compact size are important. Embedded audio for microcontroller projects, single board computer sound output, and DIY smart devices using I2S audio. Prototyping and demo boards where a small, lowpower digital amplifier is needed to drive small speakers. How to adjust gain By default the module provides 9 dB gain. To change gain, connect pullup or pulldown resistors or wire the gain select pin to set 3 dB, 6 dB, 9 dB, 12 dB, or 15 dB as required. This module offers a compact, efficient solution for adding digital I2S audio amplification to embedded and portable projects while providing selectable gain and basic protection features for reliable operation.