A Caltech Library Service

A Fully Intraocular High-Density Self-Calibrating Epiretinal Prosthesis

Monge, Manuel and Raj, Mayank and Nazari, Meisam Honarvar and Chang, Han-Chieh and Zhao, Yu and Weiland, James D. and Humayun, Mark S. and Tai, Yu Chong and Emami, Azita (2013) A Fully Intraocular High-Density Self-Calibrating Epiretinal Prosthesis. IEEE Transactions on Biomedical Circuits and Systems, 7 (6). pp. 747-760. ISSN 1932-4545. doi:10.1109/TBCAS.2014.2298334.

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item:


This paper presents a fully intraocular self-calibrating epiretinal prosthesis with 512 independent channels in 65 nm CMOS. A novel digital calibration technique matches the biphasic currents of each channel independently while the calibration circuitry is shared among every 4 channels. Dual-band telemetry for power and data with on-chip rectifier and clock recovery reduces the number of off-chip components. The rectifier utilizes unidirectional switches to prevent reverse conduction loss in the power transistors and achieves an efficiency > 80%. The data telemetry implements a phase-shift keying (PSK) modulation scheme and supports data rates up to 20 Mb/s. The system occupies an area of 4.5 ×3.1 mm^2. It features a pixel size of 0.0169 mm^2 and arbitrary waveform generation per channel. In vitro measurements performed on a Pt/Ir concentric bipolar electrode in phosphate buffered saline (PBS) are presented. A statistical measurement over 40 channels from 5 different chips shows a current mismatch with μ = 1.12 μA and σ = 0.53 μA. The chip is integrated with flexible MEMS origami coils and parylene substrate to provide a fully intraocular implant.

Item Type:Article
Related URLs:
URLURL TypeDescription
Monge, Manuel0000-0001-9799-0693
Humayun, Mark S.0000-0002-5830-5208
Tai, Yu Chong0000-0001-8529-106X
Emami, Azita0000-0003-2608-9691
Additional Information:© 2013 IEEE. Manuscript received October 18, 2013; revised December 10, 2013; accepted December 19, 2013. Date of publication January 20, 2014; date of current version January 28, 2014. This work was supported by NSF Biomimetic Micro-Electronic Systems—Engineering Research Center (BMES-ERC). This paper was recommended by Associate Editor S. Gambini. The authors acknowledge the contributions of M. Loh and J. Yoo for insightful technical discussions, A. Wang for assistance with the experimental work, and TSMC for chip fabrication.
Funding AgencyGrant Number
Subject Keywords:Biomedical, calibration, data telemetry, epiretinal prosthesis, implantable biomedical devices, neural interfaces, neural prosthesis, neural stimulator, neurostimulator, power telemetry, retinal prosthesis, self-calibrating.
Issue or Number:6
Record Number:CaltechAUTHORS:20140225-114331568
Persistent URL:
Official Citation:Monge, M.; Raj, M.; Nazari, M.H.; Han-Chieh Chang; Yu Zhao; Weiland, J.D.; Humayun, M.S.; Yu-Chong Tai; Emami, A., "A Fully Intraocular High-Density Self-Calibrating Epiretinal Prosthesis," Biomedical Circuits and Systems, IEEE Transactions on , vol.7, no.6, pp.747,760, Dec. 2013 doi: 10.1109/TBCAS.2014.2298334
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:43982
Deposited By: Ruth Sustaita
Deposited On:25 Feb 2014 21:00
Last Modified:10 Nov 2021 16:46

Repository Staff Only: item control page