Nowadays, MEMS microspeakers are the future evolution of traditional voice-coils speakers for in-ear and hearing aids applications. Some companies have already placed on market devices fully compatible with CMOS production processes, paving the way for an industrial commercialization of these. This work, carried out within the collaboration of the department of Civil and Environmental Engineering of Politecnico di Milano and STMicroelectronics, contains a conspicuous review of the novel microspeakers appeared in the literature in the last two decades and present novel designs of electrostatic and piezoelectric microspeakers for in-ear applications. A consolidated design process flow from previous works is here used to accurately predict sound pressure outputs of two microspeakers fabricated by STMicroelectronics. The advantages of two different designs are merged together to realize the model of a new microspeaker, featuring a particular driving approach that enhances performances maintaining low power consumption. The device simulation, referred to as push-pull design, shows superior performance with respect to the other two and to devices present in literature, highlighting how much improvements in fabrication processes are key in allowing innovative and complicated design choices.
Al giorno d’oggi, i microspeakers MEMS rappresentano la futura evoluzione dei tradizionali altoparlanti magnetodinamici per applicazioni in-ear ed apparecchi acustici. Alcune aziende hanno già immesso sul mercato dispositivi pienamente compatibili con il processo produttivo CMOS, aprendo la strada ad una commercializzazione industriale di quest’ultimi. Questo lavoro, svolto in collaborazione con il Dipartimento di Ingegneria Civile e Ambientale del Politecnico di Milano e STMicroelectronics, include un’ampia rassegna dei recenti microspeakers apparsi in letteratura negli ultimi due decenni e presenta nuovi progetti di microspeakers elettrostatici e piezoelettrici per applicazioni in-ear. Fasi di progettazione consolidati da lavori precedenti vengono utilizzati per prevedere con precisione le prestazioni sonore di due microspeaker fabbricati da STMicroelectronics. I vantaggi dei due diversi progetti vengono fusi insieme per realizzare un nuovo modello di microspeaker caratterizzato da una particolare configurazione di attuazione degli elettrodi, che migliora le prestazioni mantenendo basso il consumo energetico. Le simulazioni fatte sul dispositivo, denominato push-pull, mostrano prestazioni superiori rispetto agli altri due e ai dispositivi presenti in letteratura, evidenziando quanto i miglioramenti nei processi di fabbricazione siano fondamentali per consentire scelte progettuali innovative e complesse.
Capacitive and piezoelectric microspeakers for in-ear applications
Pedercini, Leonardo
2023/2024
Abstract
Nowadays, MEMS microspeakers are the future evolution of traditional voice-coils speakers for in-ear and hearing aids applications. Some companies have already placed on market devices fully compatible with CMOS production processes, paving the way for an industrial commercialization of these. This work, carried out within the collaboration of the department of Civil and Environmental Engineering of Politecnico di Milano and STMicroelectronics, contains a conspicuous review of the novel microspeakers appeared in the literature in the last two decades and present novel designs of electrostatic and piezoelectric microspeakers for in-ear applications. A consolidated design process flow from previous works is here used to accurately predict sound pressure outputs of two microspeakers fabricated by STMicroelectronics. The advantages of two different designs are merged together to realize the model of a new microspeaker, featuring a particular driving approach that enhances performances maintaining low power consumption. The device simulation, referred to as push-pull design, shows superior performance with respect to the other two and to devices present in literature, highlighting how much improvements in fabrication processes are key in allowing innovative and complicated design choices.File | Dimensione | Formato | |
---|---|---|---|
2024_07_Pedercini_Tesi_01.pdf
non accessibile
Descrizione: Testo tesi
Dimensione
16.91 MB
Formato
Adobe PDF
|
16.91 MB | Adobe PDF | Visualizza/Apri |
2024_07_Pedercini_Executive_Summary_02.pdf
non accessibile
Descrizione: Executive summary
Dimensione
1.31 MB
Formato
Adobe PDF
|
1.31 MB | Adobe PDF | Visualizza/Apri |
I documenti in POLITesi sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/10589/222964