A precise charge balancing and compliance voltage monitoring stimulator front-end for 1024-electrodes retinal prosthesis.
In this paper, we present a precise charge balancing and compliance voltage monitoring stimulator front-end for 1024-electrode retinal prosthesis. Our stimulator is based on current mode stimulation. To generate a precisely matched biphasic current pulse, a dynamic current copying technique is applied at the stimulator front-end. A compliance voltage monitoring circuitry is included at the stimulator front-end to detect if a voltage across electrode-tissue interface goes beyond a predefined compliance voltage. Simulation results show the mismatch of a biphasic current pulse (at a maximum stimulation current of 476µA) is less than 0.1%. Also, the stimulator issues alarm signals, when a voltage compliance occurs during stimulation due to high tissue impedance. Our stimulator is implemented using a 65nm low voltage (LV) CMOS process, which helps reducing implementation area and power consumption.
Department of Electrical and Electronic Engineering, University of Melbourne, Melbourne, Australia. hosung.chun@unimelb.edu.au
Hosung
H
Chun
Nhan
N
Tran
Yuanyuan
Y
Yang
Omid
O
Kavehei
Shun
S
Bai
Stan
S
Skafidas
D004558:Electric Stimulation; D004567:Electrodes, Implanted; D004867:Equipment Design; D006801:Humans; D057488:Visual Prosthesis