Circuit for sound detector using LM 386
There is no way on earth I'd feed the output of this audio amplifier directly into a sensitive little pin of any MCU: -



The output is capacitively coupled and this means the audio signal coming from the microphone will be an AC signal into the pin and more importantly....

NO CURRENT LIMIT to protect the analogue input.

Put a 10k resistor in series with the output capacitor C4.