IEEE Trans Biomed Circuits Syst. 2019 Apr;13(2):376-386. doi: 10.1109/TBCAS.2019.2895660. Epub 2019 Jan 28.
Electrocardiogram (ECG) is one of the major physiological vital signs and an effective monitoring method for patients with cardiovascular diseases. However, existing ECG recordings require a galvanic body contact, which is unpractical in daily life. This paper presents the design of an ECG chip that facilitates non-contact ECG recording through capacitive coupling. With the input impedance boosting techniques, as well as an active driven-right-leg (DRL) which boosts common-mode rejection ratio to 70 dB, the single-ended capacitive feedback active electrode (AE) achieves ultra-high input impedance of 400 GΩ (< 0.5 Hz), a large common-mode interference tolerance (2.8 V), and a high linear-input-range (220 m V). Implemented in 0.18 μm 5V CMOS process, the prototype occupies an area of 1.23 mm, and consumes 18 μA and 13 μA for the AE and DRL, respectively. Real life non-contact capacitively coupled ECG acquisition has been demonstrated, obtaining ECG waves and heart rate in the presence of motion artifacts as well as ambient interference.
心电图（ECG）是主要的生理生命体征之一，也是心血管疾病患者的有效监测方法。然而，现有的心电图记录需要进行电偶接触，这在日常生活中并不实用。本文提出了一种心电图芯片的设计，通过电容耦合实现非接触式心电图记录。通过输入阻抗提升技术以及主动驱动右腿（DRL）技术，该单端电容反馈有源电极（AE）实现了超高输入阻抗 400 GΩ（<0.5 Hz）、大共模干扰容忍度（2.8 V）和高线性输入范围（220 mV）。该芯片采用 0.18 μm 5V CMOS 工艺实现，原型面积为 1.23 mm²，AE 和 DRL 的功耗分别为 18 μA 和 13 μA。已经演示了实际生活中非接触电容耦合心电图采集，在存在运动伪影和环境干扰的情况下获得了心电图波和心率。
