Infineon — High-Performance MEMS Microphone with 69dB(A) SNR and Lowest Distortion

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The IM69D130 is designed for applications where low self-noise (high SNR), wide dynamic range, low distortion and a high acoustic overload point is required.

IM69D130 is a high-performance digital MEMS microphone making use of Infineon’s Dual Backplate MEMS technology to deliver 105dB dynamic range and high output linearity up to 130dBSPL. The application benefits are crystal-clear audio signals, extended pick-up distance and sensitivity to both soft and loud signals – from whispered speech to rock concerts. Infineon’s Dual Backplate MEMS technology is based on a miniaturized symmetrical microphone design, similar to studio condenser microphones, and results in high linearity of the output signal within a dynamic range of 105dB. The microphone distortion does not exceed 1% even at sound pressure levels of 128dBSPL. The flat frequency response (28Hz low frequency roll-off) and tight manufacturing tolerance result in close phase matching of the microphones, which is important for multi-microphone (array) applications.

The digital microphone ASIC contains an extremely low noise preamplifier and a high-performance sigma-delta ADC. Different power modes can be selected in order to suit specific current consumption requirements. Each IM69D130 microphone is trimmed with an advanced IFX calibration algorithm, resulting in small sensitivity tolerances (±1dB). The phase response is tightly matched (±2°) between microphones, in order to support beamforming applications.

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Minimal Audio Signal Latency Enabled by an Ultra-Low Microphone Group Delay

The IM69D130 is designed to be an extremely low latency digital microphone – aimed at applications such as active noise cancellation, where audio data must be processed extremely quickly.

By delivering best-in-class group delay performance, the IM69D130 brings the system design benefits of digital microphones to many areas which had to use analog up to now.

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FEATURES

  • 69dB(A) signal-to-noise ratio
  • Below 1% distortion at 128dBSPL (130dBSPL AOP)
  • Digital (PDM) interface with 6μs group delay at 1kHz
  • Tight sensitivity (-36 ±1dB) and phase (±2°) tolerances
  • 28Hz low frequency roll-off
  • 980μA current consumption (300μA in low-power mode)

BENEFITS

  • Far field and soft audio signal pick-up
  • Clear audio signals even at high sound pressure levels
  • Enabling precise steering of audio beams for advanced audio algorithms

APPLICATIONS

  • Voice User Interface (VUI): e.g. smart speaker, home automation and IoT devices
  • Active Noise Cancellation (ANC): headphones and earphones
  • High-quality audio capturing: e.g. cameras, camcorders, conference systems
  • Audio pattern detection: industrial or home monitoring