High Performance SoundWire Microphone

The CS7257B is a low profile digital microphone with SoundWire® interface optimized for use in high performance audio systems, as well as low power audio applications featuring “always-on” voice control. The CS7257B is manufactured using Cirrus Logic’s proprietary CMOS/MEMS membrane technology offering high reliability and excellent audio quality in a miniature, low profile package. The device incorporates a SoundWire interface compatible with the MIPI SoundWire bus interface and incorporates two operational modes that can be selected according to the applied clock frequency. High performance mode offers a low noise, wide dynamic range, plus class-leading THD even with very loud audio. Low power mode offers ultra low current consumption while maintaining excellent SNR. The CS7257B offers tight tolerance on the microphone sensitivity, giving reduced variation between parts and removing the need for in-line production calibration of part-to-part microphone variations.

Innovation that Rocks® Cirrus RocksTM Cirrus®


  • High SNR (66 dB)
  • High AOP (131 dB SPL)
  • Excellent THD (1% at 125 dB SPL)
  • 35 Hz low frequency rolloff
  • Low current consumption
    • 5µA (Sleep)
    • 260 µA (low power mode)
    • 770 µA (high performance mode)
  • PDM digital audio output
  • Proprietary ADC technology
    • Reduced clock-jitter sensitivity
    • Low noise floor
    • Stable in overload condition
  • Bottom Port LGA Package

Parametric Specifications

Not Recommended for New Designs


Comprehensive Solutions