The MAX4466 is a micropower operational amplifier optimized for use as a microphone preamplifier. On the back, we include a small trimmer pot to adjust the gain. You can set the gain from 25x to 125x. That's down to be about 200mVpp (for normal speaking volume about 6“ away).

Using introduction:

• GND to ground
• VCC to 2.4-5VDC
• The audio waveform will come out of the OUT pin
• The output will have a DC bias of VCC/2 so when its perfectly quiet, the voltage will be a steady VCC/2 volts (it is DC coupled)
• If the audio equipment you're using requires AC coupled audio, place a 100uF capacitor between the output pin and the input of your device.
• If you're connecting to an audio amplifier that has differential inputs or includes decoupling capacitors, the 100uF cap is not required.

• Power supply voltage: + 2.4V to + 5.5V (can be directly connected to STM / ARDUNIO / Raspberry Pi and other development board)
• Power supply rejection ratio: 112dB
• Common mode rejection ratio: 126dB
• AVOL: 125dB (RL = 100kΩ) rail-to-rail output
• Static supply current: andlt;24μA
• Gain bandwidth: 600kHz
• Size: 20.8MM*13.8MM*7.5MM

• MAXXIM - Low-Cost, Micropower, SC70/SOT23-8, Microphone Preamplifiers with Complete Shutdown - DATASHEET [EN]