Jain Aditi, Chung Saeromi, Spencer Eliah Aronoff, Hall Drew A
IEEE Trans Biomed Circuits Syst. 2025 Apr;19(2):416-427. doi: 10.1109/TBCAS.2024.3450843. Epub 2025 Apr 2.
This paper presents a 16 × 20 CMOS biosensor array based on electrochemical impedance spectroscopy (EIS), a highly sensitive label-free technique for rapid disease detection at the point-of-care. This high-density system implements polar-mode detection with phase-only EIS measurement over a 5 kHz - 1 MHz frequency range. The design features predominantly digital readout circuitry, ensuring scalability with technology, along with a load-compensated transimpedance amplifier, all within a 140 × 140 µm pixel. The architecture enables in-pixel digitization and accumulation, which increases the SNR by 10 dB for each 10× increase in readout time. Implemented in a 180 nm CMOS process, the 3 × 4 mm chip achieves state-of-the-art performance with an rms phase error of 0.035% at 100 kHz through a duty-cycle insensitive phase detector and one of the smallest per pixel areas with in-pixel quantization.
本文介绍了一种基于电化学阻抗谱（EIS）的16×20 CMOS生物传感器阵列，EIS是一种高灵敏度的无标记技术，可在现场护理点快速进行疾病检测。这个高密度系统在5 kHz至1 MHz频率范围内通过仅相位EIS测量实现极模式检测。该设计的主要特点是数字读出电路，确保了与技术的可扩展性，以及一个负载补偿跨阻放大器，所有这些都集成在一个140×140 µm的像素内。该架构实现了像素内数字化和累加，每将读出时间增加10倍，信噪比就提高10 dB。该3×4 mm芯片采用180 nm CMOS工艺实现，通过占空比不敏感鉴相器在100 kHz时实现了0.035%的均方根相位误差，达到了当前的先进性能，并且具有像素内量化的最小像素面积之一。
