Design eines Treibers für MEMS-Lautsprecher

Microelectromechanical systems (MEMS) have already found widespread use in highly integrated audio applications. Currently, they are used for microphones where their small size has enabled the use of multiple microphones in a single device to improve noise cancellation. Nowaday, even loudspeakers realized as MEMS structures are possible, which brings up new challenges in circuit design that are the focus of this paper. Starting with an overview of current research activities of MEMS speakers, their advantages and disadvantages, as well as the peculiarities of the driver design are discussed. Compared to electrodynamic speakers, MEMS speakers have a different physical structure which needs to be accounted for when designing the driving circuitry. Possible driver concepts are presented and compared with special consideration of their efficiency and audio quality. Existing concepts are shown and new concepts are proposed.