A Complete 256-Electrode Retinal Prosthesis Chip

Tran, N.; Bai, Shun; Yang, Jiawei; Huang, Chun; Kavehei, Omid; Yang, Yuanyuan; Muktamath, V.; Ng, David C.; Meffin, Hamish; Halpern, M.E.; Skafidas, Efstratios

doi:10.1109/jssc.2014.2298037

Cited by 84 publications

(50 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Table 1 Performance of current stimulators. TBCAS 2014 (52) JSTS 2014 (54) JBN 2013 (55) JSSC 2014 (56) …”

Section: Current Stimulatorsmentioning

confidence: 99%

Contactless Liquid Sensing Technique Using a Quartz Oscillator

2016

Sensors and Materials

View full text Add to dashboard Cite

Retinal degenerative diseases result in a progressive degeneration of photoreceptors in the retina and eventually lead to complete blindness. Among the many approaches tested, electrical stimulation of the remaining retinal neurons has shown the most promising results for vision rehabilitation of the blind. However, to improve the performance of retinal prosthetic systems, the fabrication of a device with a large number of stimulation electrodes is essential. For the successful development of a high-resolution prosthetic device, it is necessary to conduct highly collaborative research on microelectrode arrays and stimulation circuits, as well as verification of this research in animal experiments. In this paper, the requirements for a high-resolution retinal prosthetic system are explained, and then research efforts from around the world including the strategies of our research group to make major breakthroughs in artificial retina research are reviewed in detail.

show abstract

“…Table 1 Performance of current stimulators. TBCAS 2014 (52) JSTS 2014 (54) JBN 2013 (55) JSSC 2014 (56) …”

Section: Current Stimulatorsmentioning

confidence: 99%

Contactless Liquid Sensing Technique Using a Quartz Oscillator

2016

Sensors and Materials

View full text Add to dashboard Cite

show abstract

“…Individual current outputs are usually unrelated and can be controlled independently up to about 1mA [2][3][4][5]. Unlike these designs, the total sum of the individual output currents in the present design is equal to a fixed value I T for each biphasic pulse, regardless the number of electrodes (between 1 and 8) being set to either cathode electrodes (E C 's) or anode electrodes (E A 's).…”

Section: Multiple-output Fixed Current Stimulation Drivermentioning

confidence: 99%

“…Variations on individual output voltages affect the voltage on node A and hence, the accuracy of I T considerably. The accuracy of I T can be improved with voltage on node A being regulated using regulated cascode technique [5][7] as shown in Fig. 4b.…”

Section: Multiple-output Fixed Current Stimulation Drivermentioning

confidence: 99%

A multiple-output fixed current stimulation ASIC for peripherally-implantable neurostimulation system

Lee

Matei

Gang

et al. 2014

Proceedings of the IEEE 2014 Custom Integrated Circuits Conference

View full text Add to dashboard Cite

A multiple-output stimulation ASIC for a peripherallyimplantable neurostimulaiton system was implemented in a 0.18µm CMOS process. The numbers of anodic outputs (NE A ) and cathodic outputs (NE C ) can be set between 1 and 8 with a fixed total output current up to 32.6mA, independent of NE A and NE C . Fast turn on technique was proposed for the stimulator to achieve a settling time of <5.8µs. The ASIC includes a power management unit and an electrode monitoring circuit, which consists of a 10-b ADC for monitoring the high voltage (~15V) stimulator outputs.

show abstract

“…For example, applying a biphasic current stimulus of A on an electrode with an electrode-tissue impedance of 50 k necessitates a minimal compliance voltage of V, but the rest of the implant, including digital control circuitry, uses low DC voltages of V, [1], [2], [5], [6]. Currently, transcutaneous inductive-powering schemes have been shown as a viable approach for power-demanding implants [1]- [5], [7]- [10]. It is thus essential to produce multiple DC voltages from a single external AC power source with high power conversion efficiency (PCE) for size-restricted implants.…”

Section: Introductionmentioning

confidence: 99%

“…of the implant is inherently increased. Two regulators following a single rectifier have also been used to generate both high and low voltages for a implant, but extra power is lost during the conversion of a induced high voltage to a low-DC voltage [10].…”

Section: Introductionmentioning

confidence: 99%

An On-Chip Multi-Voltage Power Converter With Leakage Current Prevention Using 0.18 um High-Voltage CMOS Process

Chen

Gad

et al. 2016

IEEE Trans. Biomed. Circuits Syst.

View full text Add to dashboard Cite

In this paper, we present an on-chip multi-voltage power converter incorporating of a quad-voltage timing-control rectifier and regulators to produce ±12 V and ±1.8 V simultaneously through inductive powering. The power converter achieves a PCE of 77.3% with the delivery of more than 100 mW to the implant. The proposed rectifier adopts a two-phase start-up scheme and mixed-voltage gate controller to avoid substrate leakage current. This current cannot be prevented by the conventional dynamic substrate biasing technique when using the high-voltage CMOS process with transistor threshold voltage higher than the turn-on voltage of parasitic diodes. High power conversion efficiency is achieved by 1) substrate leakage current prevention, 2) operating all rectifying transistors as switches with boosted gate control voltages, and 3) compensating the delayed turn-on and preventing reverse leakage current of rectifying switches with the proposed look-ahead comparator. This chip occupies an area of 970 μm × 4500 μm in a 0.18 μ m 32 V HV CMOS process. The quad-voltage timing-control rectifier alone is able to output a high DC voltage at the range of [2.5 V, 25 V]. With this power converter, both bench-top experiment and in-vivo power link test using a rat model were validated.

show abstract

A Complete 256-Electrode Retinal Prosthesis Chip

Cited by 84 publications

References 46 publications

Contactless Liquid Sensing Technique Using a Quartz Oscillator

Contactless Liquid Sensing Technique Using a Quartz Oscillator

A multiple-output fixed current stimulation ASIC for peripherally-implantable neurostimulation system

An On-Chip Multi-Voltage Power Converter With Leakage Current Prevention Using 0.18 um High-Voltage CMOS Process

Contact Info

Product

Resources

About