In this paper, the design and implementation of a low-power, high-resolution, fully differential readout architecture for capacitive sensing applications is presented. The proposed sensing mechanism is based on the gain variations of two capacitively coupled operational transconductance amplifiers (OTAs). The target analyte acts as the dielectric of a sensing electrode, and its detection results in capacitance variations. These capacitance variations are translated to voltage, and the result is amplified to be used as a biomarker detector. With high-gain OTAs and a high-gain difference amplifier, the proposed mechanism achieves a high-resolution of $1\mathrm{aF}$, with a sensitivity of $290\mathrm{mV}/\mathrm{fF}$. The proposed structure exhibits such a high-resolution while maintains an extremely low-power consumption of $6.6\mathrm{\mu }\mathrm{W}$. Using perfectly matched elements with accurate layout, this structure is able to reduce the mismatch-based errors to less than $0.05\%$. An 8-bit control word adjusts the sensitivity and the detection range of the proposed structure which results in a wide dynamic range of $100\mathrm{dB}$. The main features of the proposed structure such as high-resolution, high-sensitivity, low-power consumption, selective capacitance detection range and adaptive sensitivity, make this readout mechanism an ideal solution for sensitive, low-power, and accurate life science biosensors.

本文介绍了一种用于电容传感应用的低功耗，高分辨率，全差分读出架构的设计和实现。所提出的感测机制基于两个电容耦合运算跨导放大器（OTA）的增益变化。目标分析物充当传感电极的电介质，其检测结果导致电容变化。这些电容变化转化为电压，结果被放大以用作生物标记检测器。利用高增益OTA和高增益差动放大器，该机制可实现高分辨率的$\mathrm{1个}\mathrm{F}$，灵敏度为 $290\mathrm{毫伏}/\mathrm{fF}$。所提出的结构具有如此高的分辨率，同时保持了极低的功耗。$6.6\mathrm{\mu }\mathrm{w\; ^}$。使用具有精确布局的完美匹配元素，此结构能够将基于不匹配的错误减少到小于$0.05％$。一个8位的控制字可调节所提议结构的灵敏度和检测范围，从而产生宽动态范围。$100\mathrm{D\; b}$。所提出的结构的主要特征，例如高分辨率，高灵敏度，低功耗，选择性电容检测范围和自适应灵敏度，使该读出机制成为灵敏，低功耗和精确生命科学生物传感器的理想解决方案。