I²S Audio Microphone

The i2s_audio microphone platform allows you to receive audio via the the I²S Audio Component.

This platform only works on ESP32 based chips.

⚠️ Warning

Audio and voice components consume a significant amount of resources (RAM, CPU) on the device.

Crashes are likely to occur if you include too many additional components in your device’s configuration. In particular, Bluetooth/BLE components are known to cause issues when used in combination with Voice Assistant and/or other audio components.

# Example configuration entry
microphone:
  - platform: i2s_audio
    id: external_mic
    adc_type: external
    i2s_din_pin: GPIOXX

  - platform: i2s_audio
    id: adc_mic
    adc_type: internal
    adc_pin: GPIOXX

Configuration variables

• adc_type (Required, enum):

  • external : Use an external ADC connected to the I²S bus.
  • internal : Use the internal ADC of the ESP32. Only supported on ESP32, no variant support.

• channel (Optional, enum): The channel of the microphone. One of left, right, or stereo. If stereo, the output data will be twice as big, with each right sample followed by a left sample. Defaults to right.

• sample_rate (Optional, positive integer): I2S sample rate. Defaults to 16000.

• bits_per_sample (Optional, enum): The bit depth of audio samples representing real data received from the microphone. One of 8bit, 16bit, 24bit, or 32bit. Defaults to 32bit.

• bits_per_channel (Optional, enum): The bit depth of audio samples actually read from the microphone. One of 8bit, 16bit, 24bit, or 32bit. Defaults to 32bit. Setting is ignored if the legacy driver is not used.

• mclk_multiple (Optional, enum): The multiple of the MCLK frequency to the sample rate. Must be divisible by 3 if using 24 bits per sample. One of 128, 256, 384, 512. Defaults to 256.

• use_apll (Optional, boolean): I2S using APLL as main I2S clock, enable it to get accurate clock. Defaults to false.

• i2s_mode (Optional, enum): The I²S mode to use. One of primary (clock driven by the host) or secondary (clock driven by the attached device). Defaults to primary.

• i2s_audio_id (Optional, ID): The ID of the I²S Audio you wish to use for this microphone.

• correct_dc_offset (Optional, boolean): Corrects a DC offset for microphones where the audio signal’s average amplitude is not 0. Defaults to false.

• All other options from Microphone

External ADC

• i2s_din_pin (Required, Pin Schema): The GPIO pin to use for the I²S DIN/SDIN (Data In) signal, also referred to as SD/SDATA (Serial Data) or ADCDAT (Analog to Digital Converter Data).
• pdm (Optional, boolean): Set this to true if your external ADC uses PDM (Pulse Density Modulation) instead of I²S. Defaults to false.

ℹ️ Note

PDM microphones are only supported on ESP32 and ESP32-S3.

Internal ADC

ℹ️ Note

Internal ADC microphones are only supported by the legacy I²S driver on a regular ESP32, not the variants.

• adc_pin (Required, Pin Schema): The GPIO pin to use for the ADC input.

Known Devices

M5Stack Atom Echo

microphone:
  - platform: i2s_audio
    adc_type: external
    i2s_din_pin: GPIOXX
    pdm: true

RaspiAudio Muse Luxe

microphone:
  - platform: i2s_audio
    i2s_din_pin: GPIOXX
    adc_type: external
    pdm: false

ICS-43434

microphone:
  - platform: i2s_audio
    i2s_din_pin: GPIOXX
    adc_type: external
    pdm: false
    sample_rate: 48000
    bits_per_sample: 32bit
    channel: left
    use_apll: true

See also

• Microphone Components