All this functionality is implemented in a light-weight SPI interface so nearly any microcontroller can play audio from an SD card. There's also a special MIDI mode that you can boot the chip into that will read 'classic' 31250Kbaud MIDI data on a UART pin and act like a synth/drum machine - there are dozens of built-in drum and sample effects! But the chip is a pain to solder, and needs a lot of extras. That's why we spun up the best breakout, perfect for use with an Arduino but also good for other microcontrollers that just don't have the computational power to decode MP3s.
The breakout is slim enough to fit on a breadboard with 1 row of holes left over for wiring. There are 3.3v and 1.8v regulators onboard with ferrite beads and analog filtering for quality analog output. There's a microphone input port that you can wire up a line-in or mic to and record compressed audio. All 8 GPIO are broken out and they all have built in 100K pulldowns, simply connect your button from the GPIO pin to 3.3V for an active-high connection. You'll likely want to play music from a microSD card so we added a holder on-board. And since we know so many of our customers use 5V microcontrollers like the Arduino, we made the interface pins all 5V compliant with level shifters so you can use the chip at 3V or 5V power/logic!
The breakout board comes fully assembled and tested. All v1.0 boards come with two 100uF electrolytic capacitors for line-level output coupling, v2.0 have the capacitors integrated into the PCB. All kits come with some 0.1" male header you can solder to the breakout so it plugs into a breadboard and a bonus stereo headphone jack that will be handy when you want to plug headphones in!