Adafruit I2S 3W Class D Amplifier Breakout - MAX98357A

Digital I2S mono Class D amplifier breakout based on the MAX98357A, delivering up to 3 W. Accepts I2S audio directly from Raspberry Pi, ESP32, or other I2S-capable hosts.

Logical pinout · physical placement not verified

VIN
Supply voltage 2.5V-5.5V. A 5V supply gives more speaker power; 3.3V is usable for lower output power.
Type · PowerVoltage · 3.3
GND
Ground reference
Type · Ground
BCLK
I2S bit clock input.
Type · Signal
LRC
I2S left/right word-select clock input (also called LRCLK or WSEL).
Type · Signal
DIN
I2S serial data input.
Type · Signal
SD
Shutdown / channel-select pin. Low shuts down the amplifier; intermediate voltages select stereo average or right channel; high selects left channel. Breakout-board resistor defaults depend on VIN.
Type · GPIO
GAIN
Gain-select pin. Floating default is 9 dB; resistor or direct ties to GND/VIN select 15 dB, 12 dB, 6 dB, or 3 dB.
Type · Analog
SPK+
Speaker output positive; connect to speaker or transducer terminal +.
Type · Signal
SPK-
Speaker output negative; connect to speaker or transducer terminal -.
Type · Signal

Pin	Type	Function	Voltage
VIN	Power	Supply voltage 2.5V-5.5V. A 5V supply gives more speaker power; 3.3V is usable for lower output power.	3.3
GND	Ground	Ground reference
BCLK	Signal	I2S bit clock input.
LRC	Signal	I2S left/right word-select clock input (also called LRCLK or WSEL).
DIN	Signal	I2S serial data input.
SD	GPIO	Shutdown / channel-select pin. Low shuts down the amplifier; intermediate voltages select stereo average or right channel; high selects left channel. Breakout-board resistor defaults depend on VIN.
GAIN	Analog	Gain-select pin. Floating default is 9 dB; resistor or direct ties to GND/VIN select 15 dB, 12 dB, 6 dB, or 3 dB.
SPK+	Signal	Speaker output positive; connect to speaker or transducer terminal +.
SPK-	Signal	Speaker output negative; connect to speaker or transducer terminal -.

Logical pinout · physical placement not verified

Pin details

9 connections

VIN
Supply voltage 2.5V-5.5V. A 5V supply gives more speaker power; 3.3V is usable for lower output power.
PowerVoltage · 3.3
GND
Ground reference
Ground
BCLK
I2S bit clock input.
Signal
LRC
I2S left/right word-select clock input (also called LRCLK or WSEL).
Signal
DIN
I2S serial data input.
Signal
SD
Shutdown / channel-select pin. Low shuts down the amplifier; intermediate voltages select stereo average or right channel; high selects left channel. Breakout-board resistor defaults depend on VIN.
GPIO
GAIN
Gain-select pin. Floating default is 9 dB; resistor or direct ties to GND/VIN select 15 dB, 12 dB, 6 dB, or 3 dB.
Analog
SPK+
Speaker output positive; connect to speaker or transducer terminal +.
Signal
SPK-
Speaker output negative; connect to speaker or transducer terminal -.
Signal

Start wiring

I2S · I2C · Analog · 3.3 – 5 V · Breakout

Verify supply voltage and logic levels before powering up.

Module pins: VIN, GND, BCLK, LRC, DIN, GAIN. Schematik maps them to your board in the app.

Amplifiers

14 other options

MAX98357A and MAX98357 I2S class-D amps, PAM8403 and TPA2012 analog stereo amps, MAX9744 20W stereo amp, LM386 and PAM8302 mono amps, and discrete op-amp packs for signal-level work.

View all 14

Related groups

4 groups

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3D printing

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Pinout