Title :
A 232-Channel Epiretinal Stimulator ASIC
Author :
Ortmanns, Maurits ; Rocke, André ; Gehrke, Marcus ; Tiedtke, Hans-Jüergen
Author_Institution :
Albert-Ludwigs-Univ., Freiburg
Abstract :
This paper presents the architecture and design of a stimulator ASIC for a visual prosthesis. The circuit employs fully wireless operation and features 232 channels with a maximum of 116 parallel stimulations. The architecture is separated into shared global functions and locally distributed stimulation functions. High tissue impedance of epiretinal stimulation sets the need for high-voltage output compliance, which is typically as high as 22.5 V in this implementation. For implantation-ready design, full testability has been achieved, full ESD protection was implemented, and novel safety features were realized in order to combine highly flexible operation with maximum innocuousness for the patient. The overall stimulator occupies 22 mm2 in a 0.35 HVCMOS technology.
Keywords :
CMOS integrated circuits; application specific integrated circuits; biology computing; electrostatic discharge; prosthetics; ASIC; ESD protection; HVCMOS technology; distributed stimulation functions; epiretinal stimulator; global functions; high tissue impedance; high-voltage output compliance; parallel stimulations; visual prosthesis; wireless operation; Application specific integrated circuits; Electrical stimulation; Electrostatic discharge; Implants; Neural prosthesis; Protection; Retina; Testing; Visual prosthesis; Voltage; BioMEMS; ESD protection; charge balancing; current stimulator; epiretinal implant; high-voltage; neural stimulator; retinal implant; testability; visual prosthesis; voltage nullor;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2007.908693
