{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,8,24]],"date-time":"2024-08-24T08:40:35Z","timestamp":1724488835503},"reference-count":19,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,2]],"date-time":"2023-01-02T00:00:00Z","timestamp":1672617600000},"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":["2022R1A2C1012037"],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Science and ICT","award":["202017D01"]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"In this study, a pulse frequency modulation (PFM)-based stimulator is proposed for use in biomedical implantable devices. Conventionally, functional electrical stimulation (FES) techniques have been used to reinforce damaged nerves, such as retina tissue and brain tissue, by injecting a certain amount of charge into tissues. Although several design methods are present for implementing FES devices, an FES stimulator for retinal implants is difficult to realize because of the chip area, which needs to be inserted in a fovea, sized 5 mm x 5 mm, and power limitations to prevent the heat generation that causes tissue damage. In this work, we propose a novel stimulation structure to reduce the compliance voltage during stimulation, which can result in high-speed and low-voltage operation. A new stimulator that is composed of a modified high-speed PFM, a 4-bit counter, a serializer, a digital controller, and a current driver is designed and verified using a DB HiTek standard 0.18 \u03bcm process. This proposed stimulator can generate a charge up to 130 nC, consumes an average power of 375 \u00b5W during a stimulation period, and occupies a total area of 700 \u00b5m \u00d7 68 \u00b5m.<\/jats:p>","DOI":"10.3390\/s23010492","type":"journal-article","created":{"date-parts":[[2023,1,2]],"date-time":"2023-01-02T09:56:27Z","timestamp":1672653387000},"page":"492","source":"Crossref","is-referenced-by-count":0,"title":["Integrated Low-Voltage Compliance and Wide-Dynamic Stimulator Design for Neural Implantable Devices"],"prefix":"10.3390","volume":"23","author":[{"given":"Yeonji","family":"Oh","sequence":"first","affiliation":[{"name":"Department of Medical Science, Korea University, Seoul 02841, Republic of Korea"}]},{"given":"Jonggi","family":"Hong","sequence":"additional","affiliation":[{"name":"Department of Health Sciences & Technology, Gachon Advanced Institute for Health Sciences & Technology, Gachon University, Incheon 21999, Republic of Korea"}]},{"given":"Jungsuk","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Gachon University, Incheon 21936, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1016\/j.pmr.2014.05.001","article-title":"Functional Electrical Stimulation and Spinal Cord Injury","volume":"25","author":"Ho","year":"2014","journal-title":"Phys. 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