A Fully-Implantable Mems-Based Autonomous Cochlear Implant
Haluk Külah, Hasan Ulusah, Salar Chamanian, Aykan Batu, Mehmet Uğur, Muhammed Berat Yüksel, Akin M. Yilmaz, Hayri Yigit, Aziz Koyuncuoğlu, Özlem Topçu, Alper K. Soydan
Abstract
This paper reports a fully implantable, MEMS-based, low-power, energy harvesting, next generation cochlear implant (CI). The implant includes multi-frequency piezoelectric transducers for sound detection and energy harvesting, rectification and signal conditioning electronics, and RF coil for fitting and external powering. These units have outstanding performances: multi-channel transducer can generate 50.7 mV <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pp</inf> (under 100 dB SPL) and recover the daily sound speech signals; signal conditioning IC consumes outstandingly low power (<500 µW) while converting outputs signals of the transducer to biphasic pulses; piezoelectric energy harvester has the highest power density (1.5 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−3</sup> W/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> ) with generated 16.25 µW under 120 dB-A sound input; energy harvester IC, provides up to 500% more power compared to an ideal full-bridge rectifier.