Sound Reactive LED's MAX9814 Amp

Ive been working on designing a board with a Atmega328P-AU and x14 WS2812B LED’s. The entire board will be tiny (about 2x2in.) and have the Atmega and all ancillaries.

The idea of the board is light up the LED’s with the music playing. I’m heavily taking inspiration from this design. I did stray away from the original project by deciding to use a MAX9814 Amp w/ AGC and changes to the code.

I also looked to Adafruit’s schematic for design help.

I’m using a small SMD Analog Mic that has separate VCC and Output pins.

So finally my question…

The “MICBIAS” is used to power the Mic @2v up to 20mA and that’s all well and dandy but looking at other microphones the output + and VCC are shared by one pin and on mine it has a separate output pin. So im assuming MICBIAS would only connect to the VCC pin on the mic would this affect the TH @ the output? also since i have a separate output would i still need to use an A/C coupling cap?

Please see attachment for Schematic

The "MICBIAS" is used to power the Mic @2v up to 20mA and that's all well and dandy but looking at other microphones the output + and VCC are shared by one pin and on mine it has a separate output pin.

Simple... Different kinds of microphones. :wink:

The Adafruit mic is correctly described as an electret condenser. The other one one that uses separate power is a MEMs mic. The supplier has mis-described it. Not unusual from "cheap suppliers" but at least they provide the manufacturer's part number and a link to the datasheet.

Soundcards provide 5V on the signal line for an electret condenser (power shared by the signal line). MEMs mics would require a separate power supply with a soundcard/laptpop (or maybe some trickery).

BTW - Dynamic mics (like the famous Shure SM58) don't require power. Studio condenser mics run from 48V phantom power.