This paper presents the development of a micromachined dual backplate condenser microphone designed for aeroacoustic applications where a high dynamic range and high bandwidth are key requirements. The microphone consists of a circular diaphragm and two porous backplates that are each comprised of doped polysilicon. The microphone was designed using both a lumped element model of the microphone and elastic plate theory. Experimental characterization indicates a sensitivity of 282 V/Pa, a linear response up to 160 dB, a noise floor of 42 dB/rtHz at 1 kHz, a flat frequency response up to 20 kHz, and a resonant frequency of 230 kHz.
