STEVAL-STWINMA2 [STMicroelectronics]

The STEVAL-STWINMA2 microphone array expansion adds advanced audio sensing capabilities to the STEVAL-STWINKT1B (and STEVAL-STWINKT1) SensorTile Wireless Industrial Node (STWIN) kit for high frequency vibration monitoring applications.

The board includes four low-power, high signal-to-noise ratio (SNR) IMP23ABSU capacitive sensing microphones, supported by a very low drop voltage, low quiescent current, and low-noise voltage regulator, ideal for battery-powered applications such as STWIN.

The expansion board is connected via a dedicated 12-pin connector to the core system board.

The combination of STWIN and STEVAL-STWINMA2 is supported thanks to the software examples provided within the X-CUBE-MEMSMIC1 expansion software package for STM32Cube.

The package includes one example of microphone data steaming via USB and one example of ultrasound condition monitoring (UltrasoundFFT) that calculates the FFT of the analog microphone signal and streams the result to a PC GUI via USB.

The microphone sampling rate is set by default to 192 kHz whereas the microphone bandwidth is up to 80 kHz.

• Analog microphone array expansion for STEVAL-STWINKT1B (and STEVAL-STWINKT1)
• Connects to the STWIN core system board through a dedicated 12-pin connector
• 3 V to 5.5 V power supply input
• 4 mm square-shaped differential microphone array
• Four IMP23ABSU high-performance, single-ended, analog, bottom-port MEMS microphones
• LDK130 300 mA low quiescent current very low noise LDO
• Ultrasound frequency response up to 80 kHz
• On-board audio-grade quad ADC
• Serial audio interface (SAI) digital output