Adafruit Mono 2.5W Class D Audio Amplifier - PAM8302

This super small mono amplifier is surprisingly powerful - able to deliver up to 2.5 Watts into 4-8 ohm impedance speakers. Inside the miniature chip is a class D controller, able to run from 2.0V to 5.5VDC. Since the amp is a class D, it is very efficient (over 90% efficient when driving an 8Ω speaker at over half a Watt) - making it perfect for portable and battery-powered projects. It has built-in thermal and over-current protection but we could barely tell it got hot. There's even a volume trim pot so you can adjust the volume on the board down from the default 24dB gain. This board is a welcome upgrade to basic "LM386" amps!

The A+ and A- inputs of the amplifier go through 1.0uF capacitors, so they are fully 'differential' - if you don't have differential outputs, simply tie the Audio- pin to ground. The output is "Bridge Tied" - which means the output pins connect directly to the speaker pins, with no connection to ground. The output is a high frequency 250KHz square wave PWM that is then 'averaged out' by the speaker coil - the high frequencies are not heard. All the above means that you can't connect the output to another amplifier, it should drive the speakers directly. Comes with a fully assembled and tested breakout board. We also include a header to plug it into a breadboard and a 3.5mm screw-terminal block so you can easily attach/detach your speaker. You will be ready to rock in 15 minutes! The speaker is NOT included, use any 4 ohm or greater impedance speaker.

* Output Power: 2.5W at 4Ω, 10% THD, 1.5W at 8Ω, 10% THD, with 5.5V Supply

* 50dB PSRR at 1KHz

* Filterless design, with ferrite bead + capacitors on output.

* Fixed 24dB gain, onboard trim potentiometer for adjusting input volume.

* Thermal and short-circuit/over-current protection

* Low current draw: 4mA quiescent and 0.5mA in shutdown (due to pull-up resistor on SD pin)

Note: The terminal block included with your product may be blue or black. Specifications Dimensions (without 0.1" header)

* 15mm x 24mm x 2mm

* Weight: 1.4g

Resources

* PAM8302A datasheet

* Primary Guide

* EagleCAD PCB files on GitHub

* Fritzing object available in Adafruit Fritzing library