Title :
Design of a CMOS single stage dual-mode SC C/V converter for capacitive sensors
Author :
Shenjie Wang ; Merino, Josep L. ; Molina-Lopez, Francisco ; Briand, Danick ; Dehollain, Catherine
Author_Institution :
RFIC Group, Ecole Polytech. Fed. de Lausanne, Lausanne, Switzerland
Abstract :
This paper presents the design of a single stage dual-mode switched-capacitor (SC) capacitance-to-voltage converter (C2V) for the inkjet-printed capacitive humidity sensor. The specifications of C2V are optimized at the system level, emphasizing the C2V operation followed by the data converter. A closed form of the maximum output range of single stage C2V is given to avoid the cascade amplification. A gain-boosting amplifier is adopted to improve the linearity. Correlated double sampling (CDS) technique attenuates the DC offset and low frequency flicker noise. This design is simulated in 0.18 μm CMOS technology with 1.8 V supply. Post layout simulation results show 3.5 mLSB integral non-linearity (INL). Output noise powers are 230 μVrms and 290 μVrms in two modes. The entire C2V operates at 50 kHz sampling rate with 54 μW power consumption.
Keywords :
CMOS integrated circuits; amplifiers; capacitive sensors; circuit simulation; flicker noise; humidity sensors; ink jet printers; integrated circuit layout; integrated circuit noise; radiofrequency integrated circuits; switched capacitor networks; switching convertors; CDS technique; CMOS single stage dual-mode SC C2V converter design; DC offset; INL; cascade amplification; correlated double sampling technique; data converter; frequency 50 kHz; gain-boosting amplifier; inkjet-printed capacitive humidity sensor; integral non-linearity; low frequency flicker noise; post layout simulation; power 5 muW; size 0.18 mum; switched-capacitor capacitance-to-voltage converter; voltage 1.8 V; voltage 230 muV; voltage 290 muV; Decision support systems; Power capacitors; Sensitivity;
Conference_Titel :
NORCHIP, 2013
Conference_Location :
Vilnius
DOI :
10.1109/NORCHIP.2013.6702005
