Article
Engineering, Multidisciplinary
Andrzej Krupa, Marcin Lackowski, Anatol Jaworek
Summary: This paper introduces a method to measure the void fraction in two-phase flow of liquid and gas phases in small channels using a capacitance sensor. The void fraction can be directly determined from the calibration curve. This method omits intermediate steps for the determination of void fraction, distinguishing it from other direct capacitance measurement methods.
Article
Engineering, Electrical & Electronic
Marcelo Alejandro Haberman, Enrique Mario Spinelli, Ferran Reverter
Summary: This article proposes a novel supply-voltage driving (SVDR) scheme for capacitive sensor front-ends to eliminate parasitic capacitance effects. Through the use of active-shielding technique and smart driving of the amplifier supply voltage reference node, the effects of parasitic capacitance of the cable are avoided. Experimental testing demonstrates the feasibility of the circuit, which does not require bulky components and is a lower-cost solution suitable for integration.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Engineering, Electrical & Electronic
Darko Vyroubal
Summary: This novel passive interface circuit utilizes a transformer to achieve high gain for various sensors, with the gain depending on the transformer voltage ratio n. Unlike traditional applications, where the gain is proportional to n, this circuit achieves high gain with n close to 1 due to positive feedback.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Engineering, Multidisciplinary
Xing Huang, Qiyue Li, Haiqian Li, Xin'ao Wei, Xiaomu Liao, Xiang Zhang
Summary: This study quantifies the influence of circuit capacitance (C) on the measurement results of PVDF piezoelectric sensors. The voltage output models in charge mode and current mode are established and verified. It is found that the influence of C on the output voltage is independent of PVDF area, piezoelectric constant, and loading rate in current mode, while in charge mode, it is determined by the ratio of C to total capacitance.
Article
Chemistry, Analytical
Shengle Ren, Mingyuan Ren, Honghai Xu
Summary: In recent years, the application of gas sensors has been expanding in various fields. To meet the requirements of miniaturization, integration, and intelligence driven by potential applications like the Internet of Things, this paper proposes a MEMS gas sensor interface circuit based on ADC technology. The proposed circuit overcomes the bottleneck in interface circuit research, enabling detection of resistance changes from 100 ohms to 1 megaohm with a conversion error within the range of 0.5% to 1%. It operates at a working voltage of 3.3V and has a maximum power consumption of 986 muW. The layout area is 0.49 x 0.77 mm(2). Post-layout simulation verifies the functionality of the circuit.
Article
Biochemistry & Molecular Biology
Alexey V. V. Butko, Vladimir Y. Y. Butko, Yurii A. A. Kumzerov
Summary: The correct formula for double-layer capacitance (C-dl) in graphene interfaces with liquid is controversial. We proposed a model that considers the capacitance of a charge accumulation layer (C-ca) and a capacitance-limiting edge region (C-e) with negligible electric susceptibility and conductivity. These capacitances are connected in series, and C-dl can be obtained from 1/C-dl = 1/C-ca + 1/C-e. Experimental results on the graphene/water interface capacitance imply that the distance from charge carriers in graphene to molecular charges at the interface is around 0.05-0.1 nm. The generalized model predicts a capacitance upper limit of approximately 18 μF/cm2.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Computer Science, Information Systems
Xinquan Lai, Yuheng Wang, Qinqin Li, Kashif Habib
Summary: The paper proposes a reset noise sampling feedforward (RNSF) technique to reduce the noise floor of MEMS capacitive accelerometers. The RNSF technique effectively suppresses the noise from parasitic capacitance, resulting in improved noise performance. Simulation and measurement results demonstrate the effectiveness of the RNSF technique in reducing noise floor.
Article
Engineering, Electrical & Electronic
Jose A. Hidalgo-Lopez
Summary: This article introduces a new circuit that directly interfaces a capacitive sensor affected by parasitic series resistances to a digital processor (DP). The circuit only requires minimal hardware components and takes advantage of the presence of DPs in many applications. By using the new circuit, the power consumption and measurement time are reduced, while achieving accurate estimation of sensor capacitance. The circuit has been implemented and evaluated using a field-programmable gate array (FPGA).
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
Yuxin Qin, Hongcheng Xu, Siyu Li, Dandan Xu, Weihao Zheng, Weidong Wang, Libo Gao
Summary: This study successfully develops a flexible dual-mode capacitive sensor that combines proximity and pressure sensing, and enables wireless sensing. The sensor is fabricated using low-cost screen printing and laser engraving methods, and exhibits features such as high detection distance, extended operating range, low detection limit, and fast response time.
IEEE SENSORS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Marcelo A. Haberman, Enrique M. Spinelli, Ferran Reverter
Summary: The novel front-end circuit for remote grounded capacitive sensors is insensitive to input capacitance and stray interconnecting-cable capacitances, achieving high accuracy and sensitivity. With the use of a properly shielded custom transformer, the circuit can maintain a nonlinearity error below 0.01% even with up to 12-m interconnecting cables.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Engineering, Electrical & Electronic
Kaushal Kishore, Nidhi Chaturvedi, S. A. Akbar
Summary: This paper introduces an improved interface system using a full Wilson current mirror with auto-balancing technique for HEMT-based biochemical sensors, which has been experimentally verified to be effective for sensors with large offset currents. The proposed circuit showed good performance with a relative error of less than +/- 2% and tunable measurement range, demonstrating its potential use for a wide range of HEMT-based sensors.
INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS
(2021)
Article
Automation & Control Systems
Kyeongsik Nam, Hyungseup Kim, Gyuri Choi, Mookyoung Yoo, Hyoungho Ko
Summary: This paper presents a low-noise incremental delta-sigma analog front end integrated circuit for capacitive microsensors. By utilizing a capacitor polarity swapping technique, the circuit achieves low-noise and high linearity, while maintaining a small active area and low power consumption.
MEASUREMENT & CONTROL
(2022)
Article
Engineering, Electrical & Electronic
Shahid Malik, Laxmeesha Somappa, Meraj Ahmad, Tarikul Islam, Maryam Shojaei Baghini
Summary: This paper presents an incremental delta-sigma based capacitance-to-digital converter for lossy capacitive sensors, which reduces measurement errors caused by variations in excitation signal frequency and amplitude through the introduced reference signal. Experimental results demonstrate the circuit's ability to accurately measure sensor capacitance and provide a high signal-to-noise ratio.
SENSORS AND ACTUATORS A-PHYSICAL
(2021)
Article
Engineering, Electrical & Electronic
Xiangyu Li, Pengjun Wang, Gang Li, Li Ni, Yuejun Zhang
Summary: The article proposes a novel high-precision interface circuit with an optimized chopper technique and switched-capacitor modulator for tunneling magnetoresistance (TMR) sensors. The circuit uses the inherent variations of TMR sensors to generate a lightweight physically unclonable function (PUF). It achieves high performance in terms of signal-to-noise ratio (SNR) and spurious-free dynamic range (SFDR).
IEEE SENSORS JOURNAL
(2023)
Article
Chemistry, Physical
C. M. Marianno, E. A. Ordonez, J. W. King, R. Suh
Summary: Based on the research findings, prolonged exposure of PVT scintillators to varying environmental conditions can lead to internal fogging and reduction in light transmission, affecting the performance of radiation portal monitors (RPMs) that utilize these detectors. The Optical Monitoring System (OMS) was able to track changes in PVT opacity and provide early indication of reduced performance in RPMs.
RADIATION PHYSICS AND CHEMISTRY
(2021)
