The 4×3mm devices are designed for applications that require low self-noise, wide dynamic range, low distortion and a high acoustic overload point. The microphones incorporate Infineon’s dual-backplate MEMS technology to enable high linearity of the output signal within a dynamic range of up to 105 dB. The dual-backplate MEMS technology is based on a miniaturized symmetrical microphone design, similar as utilized in studio condenser microphones, which generates a truly differential signal. The technology allows improved high frequency immunity for better audio signal processing and increases the acoustic overload point of 10-percent total harmonic distortion (THD) to 135 dB SPL. Noise floor is just 25 dBA (69 dBA signal-to-noise ratio (SNR)), with distortion less than 1 percent, even at sound pressure levels of 128 dB SPL. For design agility, the IM69D120 microphone has been specifically designed to preserve the 69 dBA SNR within the dynamic range of a 16-bit system, whereas the IM69D130 is suitable for 20-bit systems.
Mouser Electronics – www.mouser.com