Chi Yu M, Cauwenberghs Gert
Department of Electrical and Computer Engineering, University of California, San Diego, CA 92092, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:4218-21. doi: 10.1109/IEMBS.2009.5333527.
A non-contact EEG electrode with input capacitance neutralization and common-mode noise suppression circuits is presented. The coin sized sensor capacitively couples to the scalp without direct contact to the skin. To minimize the effect of signal attenuation and channel gain mismatch, the input capacitance of each sensor is actively neutralized using positive feedback and bootstrapping. Common-mode suppression is achieved through a single conductive sheet to establish a common mode reference. Each sensor electrode provides a differential gain of 60 dB. Signals are transmitted in a digital serial daisy-chain directly from a local 16-bit ADC, minimizing the number of wires required to establish a high density EEG sensor network. The micropower electrode consumes only 600 microW from a single 3.3 V supply.
本文提出了一种具有输入电容中和及共模噪声抑制电路的非接触式脑电图电极。这种硬币大小的传感器通过电容耦合至头皮，而无需直接接触皮肤。为了最小化信号衰减和通道增益失配的影响，每个传感器的输入电容通过正反馈和自举进行主动中和。共模抑制通过单个导电片来建立共模参考得以实现。每个传感器电极提供60 dB的差分增益。信号直接从本地16位模数转换器以数字串行菊花链的方式传输，从而将建立高密度脑电图传感器网络所需的导线数量减至最少。该微功耗电极从单个3.3 V电源仅消耗600微瓦的功率。
