A 3.3V 15.6b 6.1pJ/0.02%RH with 10ms response humidity sensor for respiratory monitoring

Author

Lai, Kelvin Yi-Tse ; Yu-Tao Yang ; Bang-Jing Chen ; Chun-Jen Shen ; Ming-Feng Shiu ; Zih-Cheng He ; Hsie-Chia Chang ; Chen-Yi Lee

Author_Institution

Dept. of Electron. Eng. & Inst. of Electron., Nat. Chiao-Tung Univ., Hsinchu, Taiwan

fYear

2014

fDate

10-12 Nov. 2014

Firstpage

293

Lastpage

296

Abstract

An event-driven and energy-efficient humidity sensor for environment detection and healthcare monitoring is presented. A differential CMOS-MEMS humidity device and proportion-based capacitance-to-digit readout circuit are proposed to overcome PVT variations, and in the meantime to improve sensitivity, response time, and conversion energy. This chip achieves 15.6b 20-90 %RH at 1KS/s, 6.1pJ per 0.02%RH of sensitivity, and 10ms fast response time in TSMC 0.35-μm CMOS MEMS process. With variations in temperature and voltage, our proposal can minimize the errors from 40%RH to 0.2%RH and 50%RH to 0.1%RH, making it very suitable for wearable respiratory monitoring.

Keywords

CMOS integrated circuits; biomedical transducers; health care; humidity measurement; humidity sensors; microsensors; patient monitoring; readout electronics; PVT variation; TSMC CMOS MEMS process; differential CMOS-MEMS humidity device; energy conversion; energy-efficient humidity sensor; environment detection; event-driven humidity sensor; healthcare monitoring; proportion-based capacitance-to-digit readout circuit; size 0.35 mum; time 10 ms; voltage 3.3 V; wearable respiratory monitoring; word length 15.6 bit; Capacitance; Humidity; Micromechanical devices; Monitoring; Sensitivity; Sensors; Time factors; Capacitive Sensing; Health-Care; Humidity Sensor; Low Energy; Low Power; Respiratory Monitoring;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Circuits Conference (A-SSCC), 2014 IEEE Asian

Conference_Location

KaoHsiung

Print_ISBN

978-1-4799-4090-5

Type

conf

DOI

10.1109/ASSCC.2014.7008918

Filename

7008918