In this article, we present the design and analysis of a 785-nW multimodal sensor interface IC for ozone pollutant sensing and correlated cardiovascular disease monitoring based on electrocardiography (ECG) and photoplethysmography (PPG). The proposed hybrid $dc$ offset current cancellation (DCOC) along with a 4- $\text{M}\Omega $ gain-regulated cascode transimpedance amplifier (RGC-TIA) enable PPG readout power reduction by $37\times $ , compared with the state-of-the-art PPG sensor interfaces. The ozone sensing channel proposes an adaptive architecture to enable low $V_{\text {DD}}$ operation, achieving a $300\times $ power reduction, compared with the state-of-the-art gas sensing readouts. The ozone sensing channel’s performance was also verified using custom resistive metal-oxide sensors for concentrations from 50 to 900 ppb. The sensor interface IC is fabricated in a 65-nm CMOS, integrating a 165-nW voltage-mode ECG channel, a 532-nW current-mode PPG channel, 76-nW resistive-mode ozone channel, and 12.6-nW peripheral circuits, all at 0.6 V. The total system power consumption including the LED and a custom digital readout IC is 10.98– $15.51~\mu \text{W}$ , which is $41\times $ – $57\times $ less than prior ozone/CVD joint monitoring sensor interface systems.

中文翻译：

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0.6V 785nW多模式传感器接口IC，用于臭氧污染感测和相关的心血管疾病监测

在本文中，我们介绍了基于心电图（ECG）和光电容积描记法（PPG）的用于臭氧污染物感测和相关心血管疾病监测的785 nW多模式传感器接口IC的设计和分析。拟议的混合动力 $ dc $ 失调电流消除（DCOC）以及4- $ \ text {M} \ Omega $ 增益调节共源共栅跨阻放大器（RGC-TIA）可通过以下方式降低PPG的读出功率： $ 37 \次$ ，与最新的PPG传感器接口相比。臭氧感测通道提出了一种自适应架构，以实现低排放 $ V _ {\ text {DD}} $ 操作，实现了 $ 300 \次$ 与最新的气体感应读数相比，功率降低。臭氧感应通道的性能也使用定制的电阻式金属氧化物传感器进行了验证，浓度范围为50到900 ppb。传感器接口IC是在65nm CMOS中制造的，集成了165nW电压模式ECG通道，532nW电流模式PPG通道，76nW电阻模式臭氧通道和12.6nW外围电路，全部为0.6V。包括LED和定制数字读出IC在内的系统总功耗为10.98– $ 15.51〜\ mu \ text {W} $ ，这是 $ 41 \次$ – $ 57 \次$ 比以前的臭氧/ CVD联合监测传感器接口系统少。