Readout Circuits for Capacitive Sensors

The development of microelectromechanical system (MEMS) processes enables the integration of capacitive sensors into silicon integrated circuits. These sensors have been gaining considerable attention as a solution for mobile and internet of things (IoT) devices because of their low power consumption. In this study, we introduce the operating principle of representative capacitive sensors and discuss the major technical challenges, solutions, and future tasks for a capacitive readout system. The signal-to-noise ratio (SNR) is the most important performance parameter for a sensor system that measures changes in physical quantities; in addition, power consumption is another important factor because of the characteristics of mobile and IoT devices. Signal power degradation and noise, which degrade the SNR in the sensor readout system, are analyzed; circuit design approaches for degradation prevention are discussed. Further, we discuss the previous efforts and existing studies that focus on low power consumption. We present detailed circuit techniques and illustrate their effectiveness in suppressing signal power degradation and achieving lower noise levels via application to a design example of an actual MEMS microphone readout system.

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Reliability Improvement of LoRa with ARQ and Relay Node

Symmetry ◽

10.3390/sym12040552 ◽

2020 ◽

Vol 12 (4) ◽

pp. 552 ◽

Cited By ~ 1

Author(s):

Rocksan Choi ◽

SeungGwan Lee ◽

Sungwon Lee

Keyword(s):

Power Consumption ◽

Low Power ◽

Smart Cities ◽

Wide Area ◽

Forward Rate ◽

Low Power Consumption ◽

Modern World ◽

Automatic Repeat Request ◽

Actual Performance ◽

Iot Devices

In our modern world, many Internet of Things (IoT) technologies are being researched and developed. IoT devices are currently being used in many fields. IoT devices use Wi-Fi and Bluetooth, however, communication distance is short and battery consumption is high. In areas such as smart cities and smart farms, IoT technology is needed to support a wide coverage with low power consumption. Low Power Wide Area (LPWA), which is a transmission used in IoT supporting a wide area with low power consumption, has evolved. LPWA includes Long Range (LoRa), Narrowband (NB-IoT), and Sigfox. LoRa offers many benefits as it communicates the longest distances, is cheap and consumes less battery. LoRa is used in many countries and covers a range of hundreds of square kilometers (km2) with a single gateway. However, if there are many obstacles to smart cities and smart farms, it causes communication problems. This paper proposes two (2) solutions to this problem: the relay method which is a multi-hop method and the Automatic Repeat Request (ARQ) system that detects packet loss in real-time and requests retransmission for LoRa. In this study, the actual performance of LoRa in the problematic environment was measured and the proposed method was applied. It was confirmed that the transmission rate of LoRa dropped when there were many obstacles such as trees. To use LoRa in a smart farm with a lot of space, multi-hop was observed to be better. An ARQ system is needed to compensate for the unexpected drop in the forward rate due to the increase in IoT devices. This research focused on reliability, however, additional network methods and automatic repeat request (ARQ) systems considering battery time should be researched in symmetry. This study covers the interdisciplinary field of computer science and wireless low power communication engineering. We have analyzed the LoRa/LoRaWAN technology in an experimental approach, which has been somewhat less studied than cellular network or WiFi technology. In addition, we presented and improved the performance evaluation results in consideration of various local and climatic environments.

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CMOS Future for Microelectronic Circuits: Low power consumption of complementary metal-oxide-semiconductor integrated circuits drives next stage of ultraminiaturization

Science ◽

10.1126/science.224.4650.705 ◽

1984 ◽

Vol 224 (4650) ◽

pp. 705-707 ◽

Cited By ~ 7

Author(s):

A. L. ROBINSON

Keyword(s):

Integrated Circuits ◽

Metal Oxide ◽

Power Consumption ◽

Low Power ◽

Complementary Metal Oxide Semiconductor ◽

Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

Low Power Consumption

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A fast, low power consumption readout system for a space based calorimeter

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/0168-9002(89)90653-0 ◽

1989 ◽

Vol 276 (1-2) ◽

pp. 367-370

Author(s):

G. Basini ◽

F. Bongiorno ◽

A. Morselli ◽

M. Occhigrossi ◽

M. Ricci ◽

...

Keyword(s):

Power Consumption ◽

Low Power ◽

Low Power Consumption ◽

Readout System

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SENSING DURATION OF LEAF MOISTURE RETENTION USING ELECTRICAL IMPEDANCE GRIDS

Canadian Journal of Plant Science ◽

10.4141/cjps78-027 ◽

1978 ◽

Vol 58 (1) ◽

pp. 179-187 ◽

Cited By ~ 89

Author(s):

T. J. GILLESPIE ◽

G. E. KIDD

Keyword(s):

Integrated Circuits ◽

Power Consumption ◽

Low Power ◽

Electrical Impedance ◽

Maximum Error ◽

Low Power Consumption ◽

Leaf Wetness ◽

Moisture Retention ◽

Remote Locations ◽

Allium Cepa L

The duration of moisture retention on mock leaf sensors made from electrical impedance grids was purposely manipulated by changing the color and angle of deployment of these sensors. The duration of moisture retention varied up to 2 h 50 min, depending on the type of moisture deposited (rain or dew) and the conditions during drying. Comparisons were made with onion (Allium cepa L.) foliage where a very light gray mock leaf indicated complete drying of the crop with a maximum error of 27 min while a DeWit Leafwet Recorder had a maximum error of 90 min. A simple AC-powered circuit for recording leaf wetness is described. Also, for use in remote locations, a battery-powered system was constructed that utilized integrated circuits for low power consumption.

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Research and Design of Low Power Consumption Testing Generator for Integrated Circuits

2010 Third International Conference on Information and Computing ◽

10.1109/icic.2010.357 ◽

2010 ◽

Cited By ~ 1

Author(s):

Yi Wang

Keyword(s):

Integrated Circuits ◽

Power Consumption ◽

Low Power ◽

Low Power Consumption ◽

Research And Design

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High speed and low power consumption DMT integrated circuits based on direct-coupled FET logic circuits

10.1109/iedm.1989.74240 ◽

2003 ◽

Author(s):

M. Fujii ◽

H. Hida ◽

Y. Tsukada ◽

Y. Ogawa ◽

M. Kohno ◽

...

Keyword(s):

Integrated Circuits ◽

Power Consumption ◽

Low Power ◽

High Speed ◽

Logic Circuits ◽

Low Power Consumption

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Designing ALU using GDI method

International Journal of Reconfigurable and Embedded Systems (IJRES) ◽

10.11591/ijres.v8.i3.pp151-161 ◽

2019 ◽

Vol 8 (3) ◽

pp. 151

Author(s):

Mohammadreza Fadaei

Keyword(s):

Integrated Circuits ◽

Power Consumption ◽

Low Power ◽

Circuit Design ◽

Cmos Technology ◽

Logic Circuits ◽

Low Power Consumption ◽

Ic Design ◽

Advantages And Disadvantages ◽

Circuit Resistance

<p>As CMOS technology is continuously becoming smaller and smaller in nanoscale regimes, and circuit resistance to changes in the process for the design of the circuit is a major obstacle. Storage elements such as memory and flip-flops are particularly vulnerable to the change process. Power consumption is also another challenge in today's Digital IC Design. In modern processors, there are a large number of transistors, more than a billion transistors, which increases the temperature and the breakdown of its performance. Therefore, circuit design with low power consumption is a critical need for integrated circuits today. In this study, we deal with GDI techniques for designing logic and arithmetic circuits. We show that this logic in addition to low power consumption has little complexity so that arithmetic and logic circuits can be implemented with fewer transistors. Various circuits such as adders, differentiation and multiplexers, etc. have been designed and implemented using these techniques, and published in various articles. In this study, we review and evaluate the advantages and disadvantages of these circuits.</p>

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Optimal design of a high homogeneous and small-size shim coil for atomic spin gyroscope based on 0-1 linear programming

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209319 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 165-172

Author(s):

Dongge Deng ◽

Mingzhi Zhu ◽

Qiang Shu ◽

Baoxu Wang ◽

Fei Yang

Keyword(s):

Linear Programming ◽

Power Consumption ◽

Low Power ◽

Optimization Design ◽

Structural Parameters ◽

Axial Position ◽

Low Power Consumption ◽

Optimal Method ◽

Atomic Spin ◽

Shim Coil

It is necessary to develop a high homogeneous, low power consumption, high frequency and small-size shim coil for high precision and low-cost atomic spin gyroscope (ASG). To provide the shim coil, a multi-objective optimization design method is proposed. All structural parameters including the wire diameter are optimized. In addition to the homogeneity, the size of optimized coil, especially the axial position and winding number, is restricted to develop the small-size shim coil with low power consumption. The 0-1 linear programming is adopted in the optimal model to conveniently describe winding distributions. The branch and bound algorithm is used to solve this model. Theoretical optimization results show that the homogeneity of the optimized shim coil is several orders of magnitudes better than the same-size solenoid. A simulation experiment is also conducted. Experimental results show that optimization results are verified, and power consumption of the optimized coil is about half of the solenoid when providing the same uniform magnetic field. This indicates that the proposed optimal method is feasible to develop shim coil for ASG.

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