Design of CMOS Instrumentation Amplifier Using Three-Stage Operational Amplifier for Low Power Signal Processing

Carbon nanotube (CNT) is one of the embryonic technologies within recent inventions towards miniaturization of semiconductor devices and is gaining much attention due to very high throughput and very extensive series of applications in various analog/mixed signal applications of today’s high-speed era. The carbon nanotube field effect transistors (CNFETs) have been reconnoitred as the stimulating aspirant for the future generations of integrated circuit (IC) devices. CNFETs are being widely deliberated as probable replacement to silicon MOSFETs also. In this paper, different analog signal processing applications such as inverting amplifier, noninverting amplifier, summer, subtractor, differentiator, integrator, half-wave and full-wave rectifiers, clipper, clamper, inverting and noninverting comparators, peak detector, and zero crossing detector are implemented using low-power folded cascode operational amplifier (op-amp) implemented using CNFET. The proposed CNFET-based analog signal processing applications are instigated at 32 nm technology node. Simulation results show that the proposed applications are properly implemented using novel folded cascode operational amplifier (FCOA) implemented using CNFET.

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Improvement of Gain Accuracy and CMRR of Low Power Instrumentation Amplifier Using High Gain Operational Amplifiers

Micro and Nanosystems ◽

10.2174/1876402912666200123153318 ◽

2020 ◽

Vol 12 (3) ◽

pp. 168-174

Author(s):

Rashmi Sahu ◽

Maitraiyee Konar ◽

Sudip Kundu

Keyword(s):

Low Power ◽

Building Blocks ◽

High Gain ◽

The Other ◽

Operational Amplifiers ◽

Instrumentation Amplifier ◽

Biomedical Signals ◽

Op Amp ◽

Op Amps ◽

Multi Stage

Background: Sensing of biomedical signals is crucial for monitoring of various health conditions. These signals have a very low amplitude (in μV) and a small frequency range (<500 Hz). In the presence of various common-mode interferences, biomedical signals are difficult to detect. Instrumentation amplifiers (INAs) are usually preferred to detect these signals due to their high commonmode rejection ratio (CMRR). Gain accuracy and CMRR are two important parameters associated with any INA. This article, therefore, focuses on the improvement of the gain accuracy and CMRR of a low power INA topology. Objective: The objective of this article is to achieve high gain accuracy and CMRR of low power INA by having high gain operational amplifiers (Op-Amps), which are the building blocks of the INAs. Methods: For the implementation of the Op-Amps and the INAs, the Cadence Virtuoso tool was used. All the designs and implementation were realized in 0.18 μm CMOS technology. Results: Three different Op-Amp topologies namely single-stage differential Op-Amp, folded cascode Op-Amp, and multi-stage Op-Amp were implemented. Using these Op-Amp topologies separately, three Op-Amp-based INAs were realized and compared. The INA designed using the high gain multistage Op-Amp topology of low-frequency gain of 123.89 dB achieves a CMRR of 164.1 dB, with the INA’s gain accuracy as good as 99%, which is the best when compared to the other two INAs realized using the other two Op-Amp topologies implemented. Conclusion: Using very high gain Op-Amps as the building blocks of the INA improves the gain accuracy of the INA and enhances the CMRR of the INA. The three Op-Amp-based INA designed with the multi-stage Op-Amps shows state-of-the-art characteristics as its gain accuracy is 99% and CMRR is as high as 164.1 dB. The power consumed by this INA is 29.25 μW by operating on a power supply of ±0.9V. This makes this INA highly suitable for low power measurement applications.

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Patch-Type Vibration Visualization (PVV) Sensor System Based on Triboelectric Effect

Sensors ◽

10.3390/s21123976 ◽

2021 ◽

Vol 21 (12) ◽

pp. 3976

Author(s):

Sun Jin Kim ◽

Myeong-Lok Seol ◽

Byun-Young Chung ◽

Dae-Sic Jang ◽

Jonghwan Kim ◽

...

Keyword(s):

Signal Processing ◽

Low Power ◽

Nuclear Power ◽

Power Plants ◽

Computing System ◽

Sensor System ◽

Wireless Sensor ◽

Sensor Systems ◽

Patch Type ◽

Triboelectric Effect

Self-powered wireless sensor systems have emerged as an important topic for condition monitoring in nuclear power plants. However, commercial wireless sensor systems still cannot be fully self-sustainable due to the high power consumption caused by excessive signal processing in a mini-electronic computing system. In this sense, it is essential not only to integrate the sensor system with energy-harvesting devices but also to develop simple data processing methods for low power schemes. In this paper, we report a patch-type vibration visualization (PVV) sensor system based on the triboelectric effect and a visualization technique for self-sustainable operation. The PVV sensor system composed of a polyethylene terephthalate (PET)/Al/LCD screen directly converts the triboelectric signal into an informative black pattern on the LCD screen without excessive signal processing, enabling extremely low power operation. In addition, a proposed image processing method reconverts the black patterns to frequency and acceleration values through a remote-control camera. With these simple signal-to-pattern conversion and pattern-to-data reconversion techniques, a vibration visualization sensor network has successfully been demonstrated.

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