title: Design for a simplified cochlear implant system.
abstract: A simplified cochlear implant (CI) system would be appropriate for widespread use in developing countries. Here, we describe a CI that we have designed to realize such a concept. The system implements 8 channels of processing and stimulation using the continuous interleaved sampling (CIS) strategy. A generic digital signal processing (DSP) chip is used for the processing, and the filtering functions are performed with a fast Fourier transform (FFT) of a microphone or other input. Data derived from the processing are transmitted through an inductive link using pulse width modulation (PWM) encoding and amplitude shift keying (ASK) modulation. The same link is used in the reverse direction for backward telemetry of electrode and system information. A custom receiver-stimulator chip has been developed that demodulates incoming data using pulse counting and produces charge balanced biphasic pulses at 1000 pulses/s/electrode. This chip is encased in a titanium package that is hermetically sealed using a simple but effective method. A low cost metal-silicon hybrid mold has been developed for fabricating an intracochlear electrode array with 16 ball-shaped stimulating contacts.
authors.affiliation: School of Electrical Engineering and Computer Science, Seoul National University, Seoul 151-744, Korea. soonkwan@helios.snu.ac.kr
authors.forename: Soon Kwan
authors.initials: SK
authors.lastname: An
authors.forename: Se-Ik
authors.initials: SI
authors.lastname: Park
authors.forename: Sang Beom
authors.initials: SB
authors.lastname: Jun
authors.forename: Choong Jae
authors.initials: CJ
authors.lastname: Lee
authors.forename: Kyung Min
authors.initials: KM
authors.lastname: Byun
authors.forename: Jung Hyun
authors.initials: JH
authors.lastname: Sung
authors.forename: Blake S
authors.initials: BS
authors.lastname: Wilson
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Rebscher
authors.forename: Seung Ha
authors.initials: SH
authors.lastname: Oh
authors.forename: Sung June
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D003054:Cochlear Implants; D004599:Electric Stimulation Therapy / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008904:Miniaturization; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D049250:Speech Recognition Software; D013813:Therapy, Computer-Assisted / Q000295:instrumentation* / Q000379:methods