Davide Gironi writes:
This is a NPN Electret Condenser Microphone Preamp board design for the use with microcontrollers ADC.
In order to make an electret condenser microphone signal “readable” by a microcontroller ADC, it has to be matched the ADC specification of the microcontroller. Most of the time it means, add some gain to the signal, reduce his impedance, and bias it.
Check out the video after the break.