Paper Info
Title
An Impedance Readout IC with Ratio-Based Measurement Techniques for Electrical Impedance Spectroscopy
Abstract
This paper presents an error-tolerant and power-efficient impedance measurement scheme for bioimpedance acquisition. The proposed architecture measures the magnitude and the real part of the target complex impedance, unlike other impedance measurement architectures measuring either the real/imaginary components or the magnitude and phase. The phase information of the target impedance is obtained by using the ratio between the magnitude and the real components. This can allow for avoiding direct phase measurements, which require fast, power-hungry circuit blocks. A reference resistor is connected in series with the target impedance to compensate for the errors caused by the delay in the sinusoidal signal generator and the amplifier at the front. Moreover, an additional magnitude measurement path is connected to the reference resistor to cancel out the nonlinearity of the proposed system and enhance the settling speed of the low-pass filter by a ratio-based detection. Thanks to this ratio-based detection, the accuracy is enhanced by 30%, and the settling time is improved by 87.7% compared to the conventional single-path detection. The proposed integrated circuit consumes only 513 mu W for a wide frequency range of 10 Hz to 1 MHz, with the maximum magnitude and phase errors of 0.3% and 2.1 & DEG;, respectively.
Year
DOI
Venue
2022
10.3390/s22041563
SENSORS
Keywords
DocType
Volume
electrical impedance spectroscopy, bioimpedance, <p>real/magnitude measurement</p>, demodulator, ratio-based detection, low-complexity design
Journal
22
Issue
ISSN
Citations 
4
1424-8220
0
PageRank 
References 
Authors
0.34
0
6
Name
Order
Citations
PageRank
Song-I Cheon122.04
Soon-Jae Kweon200.68
Youngin Kim300.34
Jimin Koo400.34
Sohmyung Ha500.68
Minkyu Je633358.17