Adafruit
Stereo 20W Class D Audio Amplifier - MAX9744
A compact Class D stereo amplifier breakout based on the Maxim MAX9744. It drives two channels of 4–8 Ω speakers at up to 20 W each, powered from 4.5–14 V DC...
A compact Class D stereo amplifier breakout based on the Maxim MAX9744. It drives two channels of 4–8 Ω speakers at up to 20 W each, powered from 4.5–14 V DC. With up to 93% efficiency, it runs cool without heatsinks — ideal for portable and battery-powered audio projects.
Volume can be controlled via an included 1 kΩ trim pot (analogue) or via I²C commands from a microcontroller with 64 steps of digital volume adjustment. The board includes polarity protection, audio jacks, terminal blocks, and I²C level shifting.
Key Features
- 20 W Stereo Output – 4 Ω speakers, 12 V supply, THD+N = 10%
- Class D Efficiency – 88–93% typical, no heatsink required
- Power Supply – 4.5 V to 14 V DC via onboard barrel jack
- Audio Input – 3.5 mm stereo headphone jack, up to 3 Vpp (DC or AC coupled)
- Dual Volume Control – Analogue (1 kΩ pot included) or I²C digital (64 steps)
- Max Gain – 29.5 dB
- Low Distortion – 0.04% THD+N
- Low Power – 20 mA quiescent, 1 µA in shutdown mode
- Protection – Short-circuit, thermal overload, and click-and-pop suppression
- Spread-Spectrum Modulation – Reduces radiated RF emissions from speaker cables
Package Contents
- 1× MAX9744 amplifier breakout (SMD components pre-assembled)
- 3× 2-pin terminal blocks
- 1× 3-pin terminal block
- 1× 470 µF power filter capacitor
- 1× 1 kΩ trim pot
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- breakout
- A breakout is a small circuit board that makes a tiny or hard-to-solder component easier to connect to with standard pins. It matters because this OLED module can be wired into a microcontroller project without needing to solder directly to the display’s fine contacts.
- microcontroller
- A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.
- RF
- RF means radio frequency, referring to signals used for wireless communication and other high-frequency electronics. A low-noise, stable power supply is important for RF circuits because power noise can affect signal quality and measurements.
- Terminal block
- A connector used to join wires together in a neat, removable, or serviceable way. For this product, it helps split one power input into several outputs without soldering.
Find this product in
Audio & Video
Brands
Related Tutorials
Free guides on learn.littlebird.com.au
