Redundant safety features in a high-channel-count retinal neurostimulator.
Redundant safety features in a high-channel-count retinal neurostimulator.
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高通道数视网膜神经刺激器中的冗余安全功能。
DOI：
10.1109/biocas.2014.6981701
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Rizzo,JosephF
中科院分区：
文献类型：
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作者：
Kelly,ShawnK;Ellersick,WilliamF;Krishnan,Ashwati;Doyle,Patrick;Shire,DouglasB;Wyatt,JohnL;Rizzo,JosephF
介绍了嵌入 256 通道视网膜假体集成电路中的安全功能。视网膜的生物学和电极-组织界面的电化学要求仔细规划和设计植入式视网膜刺激装置的安全特性。我们描述了 ASIC 的内部限制和通信安全功能，但我们重点关注电极-组织界面的监控和保护电路。每个通道的两个独立电压监控电路测量双相刺激周期中两个不同时间的电极极化电压。监测器确保带电电极保持在电化学水窗口电势内，并且放电电极位于反电极电势附近的小窗口内。在脉冲之间将每个电极连接到反电极的开关可以防止各种设备故障。此外，我们描述了主动反馈系统的工作，以确保电极电压为零。
Safety features embedded in a 256-channel retinal prosthesis integrated circuit are presented. The biology of the retina and the electrochemistry of the electrode-tissue interface demand careful planning and design of the safety features of an implantable retinal stimulation device. We describe the internal limits and communication safety features of our ASIC, but we focus on monitoring and protection circuits for the electrode-tissue interface. Two independent voltage monitoring circuits for each channel measure the electrode polarization voltage at two different times in the biphasic stimulation cycle. The monitors ensure that the charged electrode stays within the electrochemical water window potentials, and that the discharged electrode is within a small window near the counter electrode potential. A switch to connect each electrode to the counter electrode between pulses protects against a wide range of device failures. Additionally, we describe work on an active feedback system to ensure that the electrode voltage is at zero.