MEMS Microphone Hookup Guide
jenfoxbot 
Hardware Overview
The SparkFun MEMS Microphone breakout board breaks out the microphone for sound detection. Each version breaks out the ADMP401 and ICS-40180 on the top side of the board. The signal is amplified with the OPA344 OpAmp.
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| Top View of ADMP401 Breakout | Top View of ICS-40180 Breakout |
The board receives audio input from the bottom of the board. There are three ports, which are labeled next to each pin.
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| Bottom View of ADMP401 Breakout | Bottom View of ICS-40180 Breakout |
- AUD - Audio signal output.
- VCC - Voltage input (1.5V to 3.3V). To power this lil' mic, use a DC voltage with a supply current of about 250μA for ADMP401 or 260μA for ICS-40180. We'll be using 3.3V from an Arduino's.
- GND - Ground.
For technically-minded folks, here are some of the features of the ADMP401 and ICS-40180. Make sure to check out datasheet for the ADMP401 or ICS-40180 for a complete overview of the microphone.
| Electrical Characteristics | ADMP401 | ICS-10480 |
|---|---|---|
| High Signal-to-Noise Ratio ("SNR") | 62 dbA | 65 dbA |
| Sensitivity | about -42 dBV | about -38 dBV |
| Flat Frequency Response | 100 Hz to 15 kHz | 60 Hz to 20 kHz |
| Low Current Consumption | <250 μA @ 3.3V | <260 μA @ 3.3V |
| Maximum Acoustic Input | 120 dB | 124 dB |
The SparkFun breakout board includes an amplifier with a gain of 67 for the ADMP401 and a gain of 65 for the ICS-10480, which is more than sufficient for the microphones. The amplifier's AUD output will float at one-half Vcc when there is no sound. When held at arms length and talked into, the amplifier will produce a peak-to-peak output of about 200 mV.
Board Dimensions
The board dimensions for the breakout are 0.55"x 0.40". The location of the audio input and header pins for each microphone is the same even though the size of the IC and locations of the components are different.
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| Board Dimensions for ADMP401 | Board Dimensions for ICS-40180 |