INMP441 MEMS microphone - I2S Interface


I would like to interface external mic/microphone on VIM3L. So far the connection is as shown in figure.

INMP441 MEMS pin Description:

  1. SCK: Serial data clock for I2S interface
  2. WS: Serial data word selection for I2S interface
  3. L/R: Left/Right channel selection.
  4. When set to low, the microphone outputs a signal on the left channel of the I2S frame.
  5. When set to high level, the microphone outputs signals on the right channel
  6. SD: Serial data output of the I2S interface.
  7. VCC: Input power, 1.8V to 3.3V.
  8. GND: power ground

I am not sure where to connect WS pin on VIM3. Moreover how can we detect any of the microphone through I2S (terminal or any Library for test). I am using Ubuntu xfce 18.04. Any suggestion please.

Thank You.

word select is the same as left/right clock so pin 32

Well I am very beginner in the Linux system, after this connections I tried to capture an audio samples (Using aplay and arecord)and found out that there was no sound card entry in cat /proc/asound/cards directory, I guess I have to write driver or modify in ALSA driver as per my understanding(pls correct if I’m wrong).

ALSA driver version is k4.9.206. in my system (Ubuntu 18.04 xfce)

So far I have been referring to this docs but seems a bit difficult to understand -

I see in alsamixer that I2S device was not detected.

Please help me with what I am missing, I am also open for any other solution for microphone.

Thank You.