Adafruit MAX98357A I2S 3W Class D Audio Amplifier Breakout

Overview

If you want clean, amplified audio from a Raspberry Pi or microcontroller without extra audio hardware, this breakout is one of the simplest ways to do it. The Adafruit MAX98357A I2S Amp Breakout takes standard I2S digital audio (the same format used inside many modern processors) and handles both jobs in one board: it converts that digital audio into analog and amplifies it to drive a speaker directly. In other words, what normally needs an I2S DAC board + an amplifier board is combined into a single compact breakout.

Unlike analog audio designs that can pick up noise, I2S keeps the signal digital until the final stage, so your project gets clear sound with fewer wiring headaches. You only need the typical I2S pins — Data, Bit Clock, and Left/Right Clock (no MCLK required) — plus power, and you’re ready to play audio files, voice prompts, alarms, and sound effects.

Even though it’s small, the amplifier is surprisingly capable. With a 5V supply and a 4Ω speaker, it can deliver up to 3.2W (at 10% THD). Because it’s a Class-D amplifier, it runs cooler and more efficiently than many linear amps, making it a great fit for portable and battery-powered builds. It also includes protection features like thermal shutdown and over-current protection for safer operation in real-world projects.

This board uses a bridge-tied-load (BTL) speaker output, meaning the speaker connects directly to the two output pins (not to ground). That’s normal for Class-D designs, but it also means you should not feed the output into another amplifier — it’s meant to drive speakers directly.

Specification

Technical details for Adafruit MAX98357A I2S 3W Class D Audio Amplifier Breakout Board

Pinout

Pinout guide for MAX98357A 3W Class D Audio Amplifier Breakout.