Abstract
This paper reports an integrated 256-channel epiretinal prosthesis integrated circuit (IC). This epiretinal prosthesis system consists of a power telemetry subsystem to deliver 100 mW power, a data telemetry subsystem to transfer 2 Mbps data, digital controllers to decode stimulation patterns, and a 256-channel stimulator to generate user programmable bi-phasic current stimuli. In this study, dual-band telemetry is adopted to achieve both high power efficiency and high data rate. Frequencies of 2 and 22 MHz are chosen for power and data carrier frequencies, respectively. A mixed-mode and multiple-voltage design is applied to the stimulator for withstanding a high-compliance voltage of ± 10 V at the output stage as well as for reducing the area of each pixel. To add flexibility to the stimulator, each pixel has a local digital controller, which enables the stimulator IC to generate 256 parallel stimulations with various pulse widths and amplitudes. The chip is fabricated in TSMC 0.18 μm 32 V CMOS process with 256 area pads constructed above the stimulus current drivers.
| Original language | English (US) |
|---|---|
| Article number | 5556426 |
| Pages (from-to) | 1946-1956 |
| Number of pages | 11 |
| Journal | IEEE Journal of Solid-State Circuits |
| Volume | 45 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 2010 |
Bibliographical note
Funding Information:Manuscript received August 11, 2009; revised December 16, 2009; accepted December 23, 2009. Date of current version August 25, 2010. This paper was approved by Associate Editor Ken Shepard. This work was supported in part by the National Science Foundation through BMES-ERC and by the Department of Energy through the Artificial Retina Project.
Keywords
- Differential phase-shift keying (DPSK)
- functional electrical stimulation (FES)
- retinal prosthesis
- telemetry