MEMS Microphones: Concept and Design for Mobile Applications
MEMS Microphones: Concept and Design for Mobile Applications
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MEMS 麦克风：移动应用的概念和设计
DOI：
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
A. Wiesbauer
中科院分区：
文献类型：
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作者：
Luca Sant;R. Gaggl;E. Bach;C. Buffa;Niccolo De Milleri;Dietmar Sträußnigg;A. Wiesbauer
尽管MEMS麦克风市场日趋成熟，但由于同一移动设备中集成了多个单元，需求仍在不断增加。此外，随着封装的不断小型化和节能，产品规格正在朝着相互矛盾的方向发展--提高信噪比(SNR)和声学过载点(AOP)。为了实现这些目标，传感器和读出电路的开发必须在密切的交互中进行，以允许权衡和定义不可移除的限制。传感器和封装的行为模型的使用允许根据声学系统的特定要求定制读出电子设备的设计，从而在噪声和功耗方面实现最佳性能。在介绍了最常用的换能器和封装电声特性映射技术后，给出了一个最先进的数字麦克风系统的设计实例，该系统的满刻度为140dBSPL，在参考电平94dBSPL时达到67dBSNR。
Despite MEMS microphone market getting more mature, the demand is still increasing due to the integration of several units in the same mobile device. Moreover, product specifications are pushing toward contradicting directions—increase of Signal-to-Noise Ratio (SNR) and Acoustic Overload Point (AOP)—with a continuous miniaturization of the package and power savings. To achieve those targets, the development of both the sensor and the readout circuitry must proceed in close interaction to allow trade-offs and define irremovable constraints. The use of behavioral models for the sensor as well as the package allows tailoring the design of the readout electronics to the specific requirements of the acoustical system, leading to the optimum performance in terms of noise and power consumption. After introducing the most commonly used techniques to map the electroacoustical properties of transducer and package, a design example of a state-of-the-art digital microphone system with 140 dB SPL full scale and achieving an SNR of 67 dB at the reference level of 94 dB SPL is presented.