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Article
Publication date: 29 March 2021

Roohie Kaushik, Jasdeep Kaur and Anushree

Reference voltage or current generators are an important requirement for an analog or digital circuit design. Bandgap reference circuits (BGR) are most common way of generating…

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Abstract

Purpose

Reference voltage or current generators are an important requirement for an analog or digital circuit design. Bandgap reference circuits (BGR) are most common way of generating the reference voltage. This paper aims to provide a detailed insight of design of a folded cascode operational amplifier (FC op amp) and a BGR circuit. The complete study flow from design to layout of the circuits on 180 nm semiconductor laboratory (SCL) process leading to bonding diagram for possible tape-out is discussed. This study work has been supported by MeitY, Govt. of India, through Special Manpower Development Project Chip to System Design.

Design/methodology/approach

This paper provides a detailed insight in design of a FC op amp and a BGR circuit. The complete study flow from design to layout of the two circuits on 180 nm SCL process leading to bonding diagram for possible tape-out is discussed. Section 2 shows the design of FC op amp, beta-multiplier circuit and their simulation results. Section 3 describes the comparison of design of conventional BGR and the proposed BGR with other state-of-art BGR circuits. Section 4 gives the comparison of their performance. The conclusion is given in Section 5.

Findings

The post-layout simulation of FC op amp show an open-loop gain of 64.5 dB, 3-dB frequency of 5.5 KHz, unity-gain bandwidth of 8.7 MHz, slew rate of 8.4 V/µs, CMRR of 111 dB and power of 25.5µW. Among the two BGR designs, the conventional BGR generated 693 mV of reference voltage with a temperature coefficient of 16 ppm/°C the other BGR, with curvature correction generated 1.3 V of reference voltage with a temperate coefficient of 6.3 ppm/°C , both results in temperature ranging from −40°C to 125°C. The chip layout of the circuits designed on 180 nm SCL process ensures design rule check (DRC), Antenna and layout versus schematic (LVS) clean with metal fill.

Research limitations/implications

Slew rate, stability analysis, power are important parameters which should be taken care while designing an op amp for a BGR. Direct current gain should be kept higher to reduce offset errors. Input common mode range is decided by the operating temperature range. A higher power supply rejection ratio will reduce BGR sensitivity to supply voltage variations. Input offset should be kept low to reduce BGR error in reference voltage. However, this paper emphasis on the flow from schematic to layout using simulation tools. As part of the study, the bonding diagram for tape-out of BGR and FC design in the given SCL frame size with seal ring is also explored, for possible tape-out.

Practical implications

Reference voltage or current generators are an important requirement for an analog or digital circuit design. BGR are most common way of generating the reference voltage. This paper provides a detailed insight in design of a FC op amp and a BGR circuit. The complete study flow from design to layout of the circuits on 180 nm SCL process leading to bonding diagram for possible tape-out is discussed. The chip layout of the circuits was designed on 180 nm SCL process ensuring DRC, antenna and LVS clean with metal fill using Cadence virtuoso and Mentor Graphics Calibre simulation tools.

Social implications

BGR are most common way of generating the reference voltage. This paper gives a detailed insight of a BGR design using a folded-cascode operational amplifier. The FC op amp is biased using a beta multiplier circuit and high-swing cascode current mirror circuit. The paper discuss FC circuit design flow from schematic to layout.

Originality/value

FC op amp is biased using a beta multiplier circuit and high-swing cascode current mirror. The paper discusses FC design flow from schematic to layout. The circuits were designed on 180 nm SCL technology with 1.8 V of power supply. The post-layout simulation show an open-loop gain of 64.5 dB, 3 dB frequency of 5.5 KHz, unity-gain bandwidth of 8.7 MHz, slew rate of 8.4 V/µs, CMRR of 111 dB and power of 25.5 µW. BGR were designed using FC op amp. The proposed BGR generated 1.3 V of reference voltage with a temperature coefficient of 6.3 ppm/°C in the range from −40°C to 125°C in schematic simulation.

Details

Circuit World, vol. 50 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 29 November 2023

Huthaifa Alqaralleh

This study explores the interconnectedness and complexity of risk-varied climate initiatives such as green bonds (GBs), emissions trading systems (ETS) and socially responsible…

134

Abstract

Purpose

This study explores the interconnectedness and complexity of risk-varied climate initiatives such as green bonds (GBs), emissions trading systems (ETS) and socially responsible investments (SRI). The analysis covers the period from September 2011 to August 2022, using six indices: three representing climate initiatives and three indicating uncertainty.

Design/methodology/approach

To achieve this, the study first examines dynamic lead-lag relations and correlation patterns in the time-frequency domain to analyse the returns of the series. Additionally, it applies an innovative approach to investigate the predictability of uncertainty measurements of climate initiatives across various market conditions and frequency spillovers in the short, medium and long run.

Findings

The findings indicate changing relationships between the series, increased linkages during turbulent market periods and strong co-movements within the network. The ETS is recommended for diversification and hedging against uncertainty indices, whereas the GB may be suitable for long-term diversification.

Practical implications

This study highlights the role of climate initiatives as potential hedges and contagion amplifiers during crises, with implications for policy recommendations and the asymmetric effects on market connectedness.

Originality/value

The paper answers questions that previous studies have not and contributes to the literature regarding financial risk management and social responsibility.

Details

The Journal of Risk Finance, vol. 25 no. 1
Type: Research Article
ISSN: 1526-5943

Keywords

Article
Publication date: 10 April 2024

Mubashir Ahmad Aukhoon, Junaid Iqbal and Zahoor Ahmad Parray

The primary objective of this study was to understand the impact of Corporate Social Responsibility on Employee Green Behavior, examining the mediating role played by Green Human…

Abstract

Purpose

The primary objective of this study was to understand the impact of Corporate Social Responsibility on Employee Green Behavior, examining the mediating role played by Green Human Resource Management Practices and the moderating influence of Employee Green Culture.

Design/methodology/approach

To accomplish this, a careful research approach was taken, using a thoughtfully designed random sampling method to encompass 300 banking employees, ensuring a robust representation of the diverse workforce in the banking sector.

Findings

The empirical findings identified green human resource management practices as a pivotal mediator and employee green culture as a significant moderator. It elucidated how the strategic implementation of green human resource management practices can act as an amplifier, strengthening the positive effects of corporate social responsibility on employee green behavior. This insight underscores the strategic importance of aligning human resource practices with sustainability goals to further enhance the environmental consciousness of employees. It was revealed that the presence of a nurturing organizational culture, one that encourages and supports environmentally responsible behaviors can significantly bolster the association between corporate social responsibility and green behavior among employees.

Originality/value

These findings underscore the essential role of organizational culture as a catalyst for the successful implementation of corporate social responsibility initiatives and the cultivation of a sustainable corporate ethos. This comprehensive research underscores the profound significance of corporate social responsibility, green human resource management practices and employee green culture in fostering and promoting environmentally responsible behaviors within the banking industry. These findings hold substantial implications not only for businesses but also for policymakers.

Details

Evidence-based HRM: a Global Forum for Empirical Scholarship, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2049-3983

Keywords

Article
Publication date: 6 October 2023

Omotayo Farai, Nicole Metje, Carl Anthony, Ali Sadeghioon and David Chapman

Wireless sensor networks (WSN), as a solution for buried water pipe monitoring, face a new set of challenges compared to traditional application for above-ground infrastructure…

Abstract

Purpose

Wireless sensor networks (WSN), as a solution for buried water pipe monitoring, face a new set of challenges compared to traditional application for above-ground infrastructure monitoring. One of the main challenges for underground WSN deployment is the limited range (less than 3 m) at which reliable wireless underground communication can be achieved using radio signal propagation through the soil. To overcome this challenge, the purpose of this paper is to investigate a new approach for wireless underground communication using acoustic signal propagation along a buried water pipe.

Design/methodology/approach

An acoustic communication system was developed based on the requirements of low cost (tens of pounds at most), low power supply capacity (in the order of 1 W-h) and miniature (centimetre scale) size for a wireless communication node. The developed system was further tested along a buried steel pipe in poorly graded SAND and a buried medium density polyethylene (MDPE) pipe in well graded SAND.

Findings

With predicted acoustic attenuation of 1.3 dB/m and 2.1 dB/m along the buried steel and MDPE pipes, respectively, reliable acoustic communication is possible up to 17 m for the buried steel pipe and 11 m for the buried MDPE pipe.

Research limitations/implications

Although an important first step, more research is needed to validate the acoustic communication system along a wider water distribution pipe network.

Originality/value

This paper shows the possibility of achieving reliable wireless underground communication along a buried water pipe (especially non-metallic material ones) using low-frequency acoustic propagation along the pipe wall.

Details

International Journal of Pervasive Computing and Communications, vol. 20 no. 2
Type: Research Article
ISSN: 1742-7371

Keywords

Article
Publication date: 7 July 2023

Martin Haupt, Stefanie Wannow, Linda Marquardt, Jana Shanice Graubner and Alexander Haas

Through activism, brands participate in the sociopolitical controversies that shape society today. Based on social identity theory, this study aims to examine the moderating…

1754

Abstract

Purpose

Through activism, brands participate in the sociopolitical controversies that shape society today. Based on social identity theory, this study aims to examine the moderating effects of consumer–brand identification (CBI) and political ideology in explaining consumer responses to brand activism. Furthermore, the role of perceived marginalization that can arise in the case of consumer–brand disagreement is explored.

Design/methodology/approach

The hypothesized effects were tested in three experiments. Study 1 (n = 262) and Study 2 (n = 322) used a moderation analysis, which was supplemented by a mixed design analysis with repeated measures in Study 1. In Study 3 (n = 383), the mediating effect of perceived marginalization by the brand was tested using a moderated mediation model.

Findings

The results show that strong CBI as well as a conservative ideology buffer the negative effects of consumer–brand disagreement on brand attitude and word-of-mouth intentions. In the case of agreement with a brand’s stance, no direct or interactive effects of brand activism on consumer responses occur. Perceived marginalization by a brand mediates the effects of brand activism.

Originality/value

This study extends the “love is blind” versus “love becomes hate” debate to the realm of brand activism and finds evidence for the former effect. It also contributes to the research on political consumption by highlighting the role of political ideology as an important boundary condition for brand activism. Perceived marginalization is identified as a relevant risk for activist brands.

Details

Journal of Product & Brand Management, vol. 32 no. 8
Type: Research Article
ISSN: 1061-0421

Keywords

Article
Publication date: 22 December 2023

Vaclav Snasel, Tran Khanh Dang, Josef Kueng and Lingping Kong

This paper aims to review in-memory computing (IMC) for machine learning (ML) applications from history, architectures and options aspects. In this review, the authors investigate…

82

Abstract

Purpose

This paper aims to review in-memory computing (IMC) for machine learning (ML) applications from history, architectures and options aspects. In this review, the authors investigate different architectural aspects and collect and provide our comparative evaluations.

Design/methodology/approach

Collecting over 40 IMC papers related to hardware design and optimization techniques of recent years, then classify them into three optimization option categories: optimization through graphic processing unit (GPU), optimization through reduced precision and optimization through hardware accelerator. Then, the authors brief those techniques in aspects such as what kind of data set it applied, how it is designed and what is the contribution of this design.

Findings

ML algorithms are potent tools accommodated on IMC architecture. Although general-purpose hardware (central processing units and GPUs) can supply explicit solutions, their energy efficiencies have limitations because of their excessive flexibility support. On the other hand, hardware accelerators (field programmable gate arrays and application-specific integrated circuits) win on the energy efficiency aspect, but individual accelerator often adapts exclusively to ax single ML approach (family). From a long hardware evolution perspective, hardware/software collaboration heterogeneity design from hybrid platforms is an option for the researcher.

Originality/value

IMC’s optimization enables high-speed processing, increases performance and analyzes massive volumes of data in real-time. This work reviews IMC and its evolution. Then, the authors categorize three optimization paths for the IMC architecture to improve performance metrics.

Details

International Journal of Web Information Systems, vol. 20 no. 1
Type: Research Article
ISSN: 1744-0084

Keywords

Article
Publication date: 24 October 2023

WenFeng Qin, Yunsheng Xue, Hao Peng, Gang Li, Wang Chen, Xin Zhao, Jie Pang and Bin Zhou

The purpose of this study is to design a wearable medical device as a human care platform and to introduce the design details, key technologies and practical implementation…

Abstract

Purpose

The purpose of this study is to design a wearable medical device as a human care platform and to introduce the design details, key technologies and practical implementation methods of the system.

Design/methodology/approach

A multi-channel data acquisition scheme based on PCI-E (rapid interconnection of peripheral components) was proposed. The flexible biosensor is integrated with the flexible data acquisition card with monitoring capability, and the embedded (device that can operate independently) chip STM32F103VET6 is used to realize the simultaneous processing of multi-channel human health parameters. The human health parameters were transferred to the upper computer LabVIEW by intelligent clothing through USB or wireless Bluetooth to complete the transmission and processing of clinical data, which facilitates the analysis of medical data.

Findings

The smart clothing provides a mobile medical cloud platform for wearable medical through cloud computing, which can continuously monitor the body's wrist movement, body temperature and perspiration for 24 h. The result shows that each channel is completely accurate to the top computer display, which can meet the expected requirements, and the wearable instant care system can be applied to healthcare.

Originality/value

The smart clothing in this study is based on the monitoring and diagnosis of textiles, and the electronic communication devices can cooperate and interact to form a wearable textile system that provides medical monitoring and prevention services to individuals in the fastest and most accurate way. Each channel of the system is precisely matched to the display screen of the host computer and meets the expected requirements. As a real-time human health protection platform technology, continuous monitoring of human vital signs can complete the application of human motion detection, medical health monitoring and human–computer interaction. Ultimately, such an intelligent garment will become an integral part of our everyday clothing.

Details

International Journal of Clothing Science and Technology, vol. 36 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 4 April 2023

Metin Şengül

In the literature, while designing broadband matching networks, transducer power gain (TPG) is used to measure the transferred power. Generally, in TPG expressions, load and…

Abstract

Purpose

In the literature, while designing broadband matching networks, transducer power gain (TPG) is used to measure the transferred power. Generally, in TPG expressions, load and back-end impedances of the matching network are used. This study aims to derive a new quality factor-based TPG expression.

Design/methodology/approach

In deriving the new expression, narrowband L type-matching network design approach is used and the new expression in terms of back-end quality factor, load quality factor and output port quality factor is obtained. Then, a broadband-matching network design approach using the derived TPG expression is proposed.

Findings

Two broadband double-matching networks are designed by using the proposed design approach using the derived TPG expression. Performances of the designed-matching networks are compared with the performances of the matching networks designed by means of simplified real frequency technique which is a well-known technique in the literature, and it is shown that they are nearly the same.

Originality/value

In broadband-matching problems, generally an impedance-based TPG expression is used, and it must be satisfied by the designed broadband-matching networks. But, in the literature, there is no quality factor-based TPG expression that can be used in broadband-matching problems. So, this gap in the literature has been filled by this paper.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 10 November 2022

Xinxing Yin, Juan Chen, Wenxin Yu, Yuan Huang, Wenxiang Wei, Xinjie Xiang and Hao Yan

This study aims to improve the complexity of chaotic systems and the security accuracy of information encrypted transmission. Applying five-dimensional memristive Hopfield neural…

Abstract

Purpose

This study aims to improve the complexity of chaotic systems and the security accuracy of information encrypted transmission. Applying five-dimensional memristive Hopfield neural network (5D-HNN) to secure communication will greatly improve the confidentiality of signal transmission and greatly enhance the anticracking ability of the system.

Design/methodology/approach

Chaos masking: Chaos masking is the process of superimposing a message signal directly into a chaotic signal and masking the signal using the randomness of the chaotic output. Synchronous coupling: The coupled synchronization method first replicates the drive system to get the response system, and then adds the appropriate coupling term between the drive The synchronization error and the coupling term of the system will eventually converge to zero with time. The synchronization error and coupling term of the system will eventually converge to zero over time.

Findings

A 5D memristive neural network is obtained based on the original four-dimensional memristive neural network through the feedback control method. The system has five equations and contains infinite balance points. Compared with other systems, the 5D-HNN has rich dynamic behaviors, and the most unique feature is that it has multistable characteristics. First, its dissipation property, equilibrium point stability, bifurcation graph and Lyapunov exponent spectrum are analyzed to verify its chaotic state, and the system characteristics are more complex. Different dynamic characteristics can be obtained by adjusting the parameter k.

Originality/value

A new 5D memristive HNN is proposed and used in the secure communication

Details

Circuit World, vol. 50 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 13 December 2022

Xuebing Su, Yang Wang, Xiangliang Jin, Hongjiao Yang, Yuye Zhang, Shuaikang Yang and Bo Yu

As it is known, the electrostatic discharge (ESD) protection design of integrated circuit is very important, among which the silicon controlled rectifier (SCR) is one of the most…

Abstract

Purpose

As it is known, the electrostatic discharge (ESD) protection design of integrated circuit is very important, among which the silicon controlled rectifier (SCR) is one of the most commonly used ESD protection devices. However, the traditional SCR has the disadvantages of too high trigger voltage, too low holding voltage after the snapback and longer turn-on time. The purpose of this paper is to design a high-performance SCR in accordance with the design window under 0.25 µm process, and provide a new scheme for SCR design to reduce the trigger voltage, improve the holding voltage and reduce the turn-on time.

Design/methodology/approach

Based on the traditional SCR, an RC-INV trigger circuit is introduced. Through theoretical analysis, TCAD simulation and tape-out verification, it is shown that RC-INV triggering SCR can reduce the trigger voltage, increase the holding voltage and reduce the turn-on time of the device on the premise of maintaining good robustness.

Findings

The RC-INV triggering SCR has great performance, and the test shows that the transmission line pulse curve with almost no snapback can be obtained. Compared with the traditional SCR, the trigger voltage decreased from 32.39 to 16.24 V, the holding voltage increased from 3.12 to 14.18 V and the turn-on time decreased from 29.6 to 16.6 ns, decreasing by 43.9% the level of human body model reached 18 kV+.

Originality/value

Under 0.25 µm BCD process, this study propose a high-performance RC-INV triggering SCR ESD protection device. The work presented in this paper has a certain guiding significance for the design of SCR ESD protection devices.

Details

Microelectronics International, vol. 41 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

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