老年性黄斑变性(Age-related Macular Degeneration, AMD)及视网膜色素变性(Retinitis Pigmentosa, RP)是视网膜退化及致盲的常见原因.研究发现，这些患者视网膜中的大部分神经细胞及视神经通路依旧完好，借助人造视网膜的电刺激有可能恢复患者的视觉.专用集成电路是人造视网膜系统中最关键的组成部分.介绍了人造视网膜系统中专用集成电路的发展，并提出了用于新一代高密度电刺激人造视网膜系统的专用集成电路体系架构，同时设计并测试了采用此体系架构的一款128通道的专用芯片.
Retina degenerations including age-related macular degeneration (AMD) and retinitis pigmentosa (RP) are common diseases causing blindness. Studies show that although the photo receptors in patients’ retina are damaged, most of the vision neurons remain attached, making current stimulation possible to restore vision. Application specific integrated circuit (ASIC) plays an important role in the development of retinal prosthesis. In this paper, the development of ASIC in retinal prosthesis is firstly reviewed. Architecture and chip designs of an ASIC for 128-channel retinal prosthesis are then introduced and the test results are presented.
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