A low-power integrated humidity CMOS sensor by printing-on-chip technology
Journal
Sensors (Switzerland)
Journal Volume
14
Journal Issue
5
Pages
9247-9255
Date Issued
2014
Author(s)
Abstract
A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene)/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
Subjects
Gas sensor; Inkjet printing; Sensor integration
Other Subjects
Chemical sensors; CMOS integrated circuits; Ethylene; Humidity sensors; Ink jet printing; Interfaces (materials); System-on-chip; Humidity sensing; Integrated sensors; Interface circuits; Practical solutions; Read-out circuit; Sensor integration; System-on-chip architecture; Three dimensional sensors; Low power electronics
Type
journal article