MH-ET LIVE INMP441 Omnidirectional MEMS Microphone Module – I2S Digital Audio

The MH-ET LIVE INMP441 Omnidirectional Microphone Module is a compact digital MEMS microphone breakout board designed for audio recording, sound detection, voice recognition, and embedded audio applications.

Featuring the INMP441 microphone sensor, the module provides a digital I2S audio output with 24-bit data resolution, eliminating the need for an external analog-to-digital converter (ADC).

With a high signal-to-noise ratio of 61dBA, a sensitivity of -26dBFS, and low current consumption of approximately 1.4mA, the module is suitable for ESP32 development boards, digital audio processing, and IoT applications.

Its omnidirectional pickup pattern allows sound detection from multiple directions, making it useful for voice-controlled devices, environmental sound monitoring, and audio-based electronics projects.

Key Features

• INMP441 MEMS Microphone: Compact digital microphone with omnidirectional sound pickup.
• Digital I2S Interface: Provides direct digital audio output to compatible microcontrollers.
• 24-Bit Audio Data: Supports high-resolution digital audio acquisition.
• High Signal-to-Noise Ratio: 61dBA SNR for low-noise audio capture.
• High Sensitivity: Typical sensitivity of -26dBFS.
• Wide Frequency Response: 60Hz to 15kHz.
• Low Power Consumption: Approximately 1.4mA typical operating current.
• High Power Supply Rejection: Listed PSR of -75dBFS.
• Left/Right Channel Selection: Allows microphone channel assignment through the L/R pin.
• Omnidirectional Pickup: Detects sound from multiple directions.
• ESP32 Compatible: Suitable for ESP32 boards with I2S receive capability.
• Compact PCB Design: Suitable for embedded audio and portable electronics projects.

Technical Specifications

Pin Configuration

Left/Right Channel Selection

The INMP441 supports channel selection using the L/R pin.

Two INMP441 microphones can share the same I2S clock and word-select signals, with one configured as the left channel and the other as the right channel.

The microphones can share the data line when configured for opposite channels, subject to the I2S interface requirements.

ESP32 Connection Example

The INMP441 can be connected directly to an ESP32 development board using its I2S interface.

Note: The GPIO assignments above are examples for a classic ESP32 development board. Other ESP32 variants may require different pin assignments and I2S configurations.

Basic Connection Instructions

1. Connect the module's VDD pin to the ESP32 3.3V supply.
2. Connect the module's GND pin to ESP32 GND.
3. Connect SCK to the selected ESP32 I2S bit clock pin.
4. Connect WS to the selected I2S word-select pin.
5. Connect SD to the selected I2S data input pin.
6. Connect L/R to GND for left-channel operation or 3.3V for right-channel operation.
7. Configure the ESP32 I2S peripheral for microphone input.
8. Read the incoming digital audio samples using an appropriate ESP32 I2S library or driver.

Arduino IDE Compatibility

The INMP441 can be used with ESP32 development boards programmed through the Arduino IDE.

Requirements:

• ESP32 development board with I2S receive support
• Arduino IDE with the appropriate ESP32 board package
• Compatible ESP32 I2S driver or library
• Correct GPIO and audio format configuration

The module outputs digital audio data and cannot be read using the standard Arduino analogRead() function.

Traditional Arduino Uno and Mega 2560 boards do not provide the same native I2S audio interface as ESP32 boards and are not recommended for direct connection without additional hardware or specialized implementation.

Applications

• ESP32 audio recording projects
• Voice recognition systems
• Voice-controlled electronics
• Smart home devices
• IoT audio monitoring
• Environmental sound detection
• Digital sound level analysis
• Audio data logging
• Speech processing experiments
• Embedded audio systems
• Educational electronics projects
• Robotics with voice interaction
• Sound-activated automation
• Digital signal processing projects
• Stereo microphone configurations

Important Notes

• The INMP441 is a digital I2S microphone, not an analog microphone module.
• It requires a compatible I2S receiver and clock signals to operate.
• The module should be powered from a suitable 3.3V supply.
• Do not connect the microphone directly to a 5V power supply or apply 5V logic signals to its pins.
• The SD pin provides digital audio data, not an analog voltage.
• The L/R pin selects the output audio channel and should be connected to a defined logic level.
• The microphone does not include a built-in speaker or audio playback amplifier.
• The module does not independently perform speech recognition or voice command processing.
• Voice recognition and audio processing require suitable software running on the connected controller or processor.
• The microphone is omnidirectional and may capture surrounding environmental noise.
• For accurate sound pressure level measurements, calibration and additional signal processing are required.
• The module is not a standalone sound level meter.
• The INMP441 requires correct I2S timing and data alignment for reliable audio acquisition.
• Raspberry Pi boards with a compatible I2S/PCM interface may be used with appropriate software configuration.
• This module is not designed for direct connection to an Arduino Uno analog input.

Package Includes

• 1 × MH-ET LIVE INMP441 Omnidirectional MEMS Microphone Module
• 1 × Pin Header Strip 

Note: The pin header may require soldering. ESP32 board, jumper wires, and other accessories are not included.