6 Pcs Max4466 Electret Microphone Amplifier Module Blue Board Breakout Product Details Using introduction: Connect 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. The output pin is not designed to drive speakers or anything but the smallest in-ear headphones- you'll need an audio amplifier (such as 3.7W stereo amp) If you want to connect the amp directly to speakers. If you're connecting to a microcontroller pin, you don't need an amplifier or decoupling capacitor - connect the OUT pin directly to the microcontroller ADC pin. For audio-reactive projects, we suggest using an FFT driver library which can take the audio input and 'translate' it into frequencies. Package Included: 2* MAX4466 Electret Microphone Amplifier Module Application scenarios: cellular phones, repeating sound device, earphones, hearing aids, microphone preamplifiers, portable computers, voice recognition systems, etc. This fully assembled and tested board comes with a 20-20KHz electret microphone soldered on. Easy to use:The board comes with a 20-20KHz electret microphone soldered on Using the MAX4466, an op-amp specifically designed for amplifier; for the best performance, use the "quietest" supply available (on an for Arduino, this would be the 3.3V supply);the amplifier has excellent power supply noise rejection Parameters: power supply voltage: +2.4V to +5.5V (can be compatible with STM, Raspberry Pi and other development board motherboards); Power supply rejection ratio: 112dB; Common mode rejection ratio: 126dB; AVOL: 125dB (RL = 100k?) rail-to-rail output; Quiescent power supply current: 24?A; Gain bandwidth: 600kHz Size:20.8MM*13.8MM*7.5MM This breakout board is best used for projects such as voice changers, audio recordingmpling, and audio-reactive or DIY projects that use FFT Payment We accept PayPal and credit cards via PayPal. Taxes - US We collect sales tax, as required by law. Shipping We make every effort of shipping within 3 business day of payment clearing. The estimated delivery time is 2 - 5 business days from the shipping date. Policies If you do need to return your item, please contact us via email (you will receive an email when your product ships with additional details - Subject: Important information about your purchase). You will then be provided with a return shipping label and packing slip. Pack the item carefully. Include the packing slip, apply the shipping label, and return the item within 30 business days of the date you request a return, or your return will be canceled. Once we receive your order we will inspect the return. Please allow up to 5 business days of receiving the returned item for your refund.