{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T14:22:31Z","timestamp":1761920551789,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,1,28]],"date-time":"2019-01-28T00:00:00Z","timestamp":1548633600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2017M3A9E2056461"],"award-info":[{"award-number":["2017M3A9E2056461"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Gachon University Gil Medical Center","award":["2016-16"],"award-info":[{"award-number":["2016-16"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a fully integrated photodiode-based low-power and low-mismatch stimulator for a subretinal prosthesis. It is known that a subretinal prosthesis achieves 1600-pixel stimulators on a limited single-chip area that is implanted beneath the bipolar cell layer. However, the high-density pixels cause high power dissipation during stimulation and high fabrication costs because of special process technologies such as the complementary metal-oxide semiconductor CMOS image sensor process. In addition, the many residual charges arising from the high-density pixel stimulation have deleterious effects, such as tissue damage and electrode corrosion, on the retina tissue. In this work, we adopted a switched-capacitor current mirror technique for the single-pixel stimulator (SPStim) that enables low power consumption and low mismatch in the subretinal device. The customized P+\/N-well photodiode used to sense the incident light in the SPStim also reduces the fabrication cost. The 64-pixel stimulators are fabricated in a standard 0.35-\u03bcm CMOS process along with a global digital controller, which occupies a chip area of 4.3 \u00d7 3.2 mm2 and are ex-vivo demonstrated using a dissected pig eyeball. According to measured results, the SPStim accomplishes a maximum biphasic pulse amplitude of 143 \u03bcA, which dissipates an average power of 167 \u03bcW in a stimulation period of 5 ms, and an average mismatch of 1.12 % between the cathodic and anodic pulses.<\/jats:p>","DOI":"10.3390\/s19030536","type":"journal-article","created":{"date-parts":[[2019,1,29]],"date-time":"2019-01-29T03:40:55Z","timestamp":1548733255000},"page":"536","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Fully Integrated Light-Sensing Stimulator Design for Subretinal Implants"],"prefix":"10.3390","volume":"19","author":[{"given":"Hosung","family":"Kang","sequence":"first","affiliation":[{"name":"Department of Medical Science, Korea University, Seoul 02841, Korea"}]},{"given":"Wajahat H.","family":"Abbasi","sequence":"additional","affiliation":[{"name":"Department of Health Science and Technology, GAIHST, Incheon 21999, Korea"}]},{"given":"Seong-Woo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Korea University Guro Hospital, Korea University College of Medicine, Seoul 08308, Korea"}]},{"given":"Jungsuk","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Health Science and Technology, GAIHST, Incheon 21999, Korea"},{"name":"Department of Biomedical Engineering, Gachon University, Incheon 21936, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2019,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2946","DOI":"10.1109\/JSSC.2007.908693","article-title":"A 232-Channel Epiretinal Stimulator ASIC","volume":"42","author":"Ortmanns","year":"2007","journal-title":"IEEE J. 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