The SparkFun Sound Detector is a small and very easy to use audio sensing board with three different outputs. The Sound Detector not only provides an audio output, but also a binary indication of the presence of sound, and an analog representation of its amplitude. The 3 outputs are simultaneous and independent, so you can use as many or as few as you want at once.
Each of the three output signals is present on the .1″ pin-out at the edge of the board. They are active simultaneously. If you arent using one in your particular application, simply leave that pin disconnected.
Resources

Schematic

Eagle Files

Datasheet(LMV324)

Hookup Guide

GitHub(Design Files)

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