1.This miniature Class D mono audio amplifier is surprisingly powerful – able to deliver up to 2.5 Watts into 4 Ohm impedance speakers, all in the form factor about the size of a US postage stamp.

2.The module features a class D audio amplifier controller IC, able to operate from 2.0V-5.5V DC input. Since the amp is class D operation, its very efficient (over 90% efficient when driving an 😯 speaker at over 1/2 Watt), making it perfect for portable and battery-powered DIY projects.

3.The module has 24dB gain, with a trim pot to adjust the volume on the board down from 24dB.

4.The A+ and A- audio inputs of the amplifier go through 1.0uF capacitors, so they are fully ‘differential’. If your audio source does not have differential outputs, simply tie the “Audio -” pin to ground.

5.The output is “Bridge Tied”, meaning that the output pins connect directly to the speaker connections with no connection to ground. The left and right channel “negative” connections should not be connected together, and the amplifier’s output should not be connected to another amplifier, it should drive the speakers directly.