How to Use SparkFun Electret Microphone Breakout: Examples, Pinouts, and Specs

The SparkFun Electret Microphone Breakout is a compact and versatile module designed to capture audio signals through its onboard electret microphone. This breakout board amplifies the weak electrical signals from the microphone, providing a usable analog output that can be easily interfaced with a variety of microcontrollers, such as the Arduino UNO, for audio detection and recording applications. Common use cases include sound level meters, audio recording, voice recognition, and simple audio-triggered systems.

• Supply Voltage (Vcc): 2.7V to 5.5V
• Output Voltage (Vout): 1.25V (typical at Vcc = 3.3V)
• Frequency Response: 20Hz to 20kHz
• Gain: Adjustable with onboard potentiometer
• Current Consumption: 2mA (typical)

1. Powering the Module:

   • Connect the VCC pin to a 2.7V to 5.5V power supply.
   • Connect the GND pin to the ground of your power supply.

2. Adjusting Gain:

   • Use the onboard potentiometer to adjust the gain as needed for your application.

3. Reading Audio Signal:

   • Connect the AUD pin to an analog input pin on your microcontroller to read the audio signal.

• Power Supply: Ensure that the power supply is within the specified range to avoid damaging the module.
• Signal Clipping: Adjust the gain to prevent the output signal from clipping at the peaks of the audio waveform.
• Noise Reduction: Keep the breakout board away from high-frequency switching devices to minimize noise.
• Analog-to-Digital Conversion: When using with a microcontroller, ensure that the analog-to-digital converter (ADC) resolution is sufficient for your application.

// Define the pin connected to the audio output
const int microphonePin = A0;

void setup() {
  // Initialize serial communication at 9600 baud rate
  Serial.begin(9600);
}

void loop() {
  // Read the analog value from the microphone
  int audioLevel = analogRead(microphonePin);

  // Print the audio level to the Serial Monitor
  Serial.println(audioLevel);

  // Delay for a short period to avoid flooding the serial output
  delay(10);
}

• Low Audio Output: If the audio output is too low, adjust the onboard potentiometer to increase the gain.
• No Audio Output: Ensure that the module is correctly powered and that the AUD pin is connected to the correct analog input on your microcontroller.
• Distorted Audio: If the audio signal is distorted, the gain may be set too high, causing clipping. Adjust the potentiometer to lower the gain.

• Check Connections: Verify that all connections are secure and correct.
• Power Supply: Confirm that the power supply voltage is within the specified range.
• Gain Adjustment: Use a screwdriver to carefully adjust the onboard potentiometer.
• Isolate Noise: Keep the microphone breakout away from noise sources such as motors or high-frequency electronics.

Q: Can I use this module with a 5V Arduino? A: Yes, the module can be powered with a 5V supply, making it compatible with 5V Arduinos.

Q: How do I adjust the gain on the module? A: Use a small screwdriver to turn the onboard potentiometer. Clockwise increases the gain, while counterclockwise decreases it.

Q: What is the purpose of the AUD pin? A: The AUD pin outputs the amplified audio signal from the microphone, which can be read by an analog input on a microcontroller.

Q: Can I connect this module directly to a speaker? A: No, the output is an analog signal meant for microcontroller ADCs. To drive a speaker, additional amplification is needed.

For further assistance, please refer to the SparkFun Electret Microphone Breakout product page and forums for community support and resources.