Adafruit Industries Stereo 3.7W Class D Audio Amplifier – MAX98306

Description

This incredibly small stereo amplifier is surprisingly powerful able to deliver 2 x 3.7W channels into 3 ohm impedance speakers. Inside the miniature chip is a class D controller, able to run from 2.7V 5.5VDC. Since the amp is a class D, its incredibly efficient (over 90percentage efficient when driving an 8Ω speaker at over 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. This board is a welcome upgrade to basic LM386 amps! The inputs of the amplifier go through 1.0uF capacitors, so they are fully ‘differential’ if you don’t have differential outputs, simply tie the R and L to ground. The outputs are Bridge Tied that means they connect directly to the outputs, no connection to ground. The output is a 360KHz 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 into another amplifier, it should drive the speakers directly.  Comes with a fully assembled and tested breakout board with 1.0uF input capacitors. We also include header to plug it into a breadboard, 3.5mm screw terminal blocks so you can easily attach/detach your speakers, and a 2×4 header + jumper to change the amplifier gain on the fly. You will be ready to rock in 15 minutes! Speakers are not included, use any 3ohm or greater impedance speakers.   Output Power: 3.7W at 3Ω, 10percentage THD, 1.7W at 8Ω, 10percentage THD, with 5V Supply Passes EMI limit unfiltered with up to 12 inches (30 cm) of speaker cable High 83dB PSRR at 217Hz Spread Spectrum Modulation and Active Emissions Limiting Five pin selectable gains: 6dB, 9dB, 12dB, 15dB and 18dB. Select with a jumper or by setting the G and G’ breakout pinsExcellent click and pop suppression