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Several ultra-low power and gigahertz current-starved voltage-controlled oscillator (CSVCO) circuits have been proposed and compared here. The presented structures are based on the three-stage hybrid circuit of the carbon nanotube field-effect transistors (CNTFETs) and low-power MOSFETs. The topologies exploit modified and compensated Schmitt trigger comparator parts to demonstrate better consumption power and frequency characteristics. The basic idea in the presented topologies is to compensate the Schmitt trigger comparator part of the basic CSVCO for achieving faster carrier mobility of the holes, reducing transistor leakage current and eliminating dummy transistors.

This study aims to propose and compare three different comparator-based VCOs that have been implemented using the CNTFETs. The considered circuits are shown to be capable of delivering the maximum 35 tuning frequency in the order of 1 GHz to 5 GHz. A major power thirsty part of the high-frequency ring VCOs is the Schmitt trigger stage. Here, several fast and low-power Schmitt trigger topologies are exploited to mitigate the dissipation power and enhance the oscillation frequency.

As a result of proposed modifications, more than one order of magnitude mitigation in the VCO power consumption with respect to the previously presented three-stage CSVCO is reported here. Thus, a VCO dissipation power of 3.5 µW at the frequency of 1.1 GHz and the tuning range of 26 per cent is observed for the well-established 32 nm technology and the supply voltage of 1 V. Such a low dissipation power is obtained around the operating frequency of the battery-powered cellular phones. In addition, using the p-carrier mobility compensation and enhancing the rise time of the Schmitt trigger part of the CSVCO, a maximum of 2.38 times higher oscillation frequency and 72 per cent wider tuning range with respect to Rahane and Kureshi (2017) are observed. Simultaneously, this topology exhibits an average of 20 per cent reduction in the power consumption.

Several new VCO topologies are presented here, and it is shown that they can significantly enhance the power dissipation of the GHz CSVCOs.

The development of a sensor microsystems containing all the components of data acquisition system, such as sensors, signal‐conditioning circuits, analog‐digital converter, interface circuits and embedded microcontroller (MCU), has become the focus of attention in many biomedical applications. A review of the microsystems technology is presented in this paper, along with a discussion of the recent trends and challenges associated with its developments. A basic description of each sub‐system is also given. This includes the different front end, mixed analog‐digital, power management, and radio transmitter‐receiver circuits. These sub‐system designs are presented and discussed in a comparative study and final remarks are made. The performance of each sub‐system is assessed regarding many aspects related to the overall system performance.

To develop a wireless sensor micro‐systems containing all the components of data acquisition system, such as sensors, signal‐conditioning circuits, analog‐digital converter, embedded microcontroller unit (MCU), and RF communication modules. This has now become the focus of attention in many biomedical applications.

The system prototype consists of miniature FSK transceiver integrated with MCU in one small package, chip antenna, and capacitive interface circuitry based on Delta‐sigma modulator. At the base station side, an FSK receiver/transmitter is connected to another MCU unit, which send the received data or received instructions from a PC through a graphical user interface GUI. Industrial, scientific and medical band RF (433 MHz) was used to achieve half duplex communication between the two sides. A digital filtering has been used in the capacitive interface to reduce noise effects forming capacitance to digital converter. All the modules of the mixed signal system are integrated in a printed circuit board of size 22.46 × 20.168 mm.

An innovation circuits and system techniques for building advanced smart medical devices have been discussed. Low‐power consumption and high reliability are among the main criteria that must be given priority when designing such wirelessly powered microsystems. Switched capacitors readout circuits have been found to be suitable for pressure sensing low‐power applications.

The presented wireless prototype needs a second phase of development that will lead to a further reduction in both size and power consumption. Currently, the main limitation of the RF system is the number of working hours according to the selected battery.

The developed system was found to be useful in terms of measuring pressure and temperature in a system of either slow or fast physical change. It would be a good idea to explore the system performance in human or animal trials.

This paper fulfils useful information for capacitive interface circuitries and presents a new short‐range wireless system that has different design features.

The purpose of this paper is to design novel hardened flip-flop using carbon nanotube field effect transistors (CNTFETs).

To design the proposed flip-flop, the Schmitt trigger-based soft error masking and unhardened latches have been used. In the proposed design, the novel mechanism, i.e. hysteresis property is used to enhance the hardness of the single event upset.

To obtain the simulation results, all the proposed circuits are extensively simulated in Hewlett simulation program with integrated circuit emphasis software. Moreover, the results of the proposed latches are compared to the conventional latches to show performance improvements. It is noted that the proposed latch shows the performance improvements up to 25.8%, 51.2% and 17.8%, respectively, in terms of power consumption, area and power delay product compared to the conventional latches. Additionally, it is observed that the simulation result of the proposed flip-flop confirmed the correctness with its respective functions.

The novel hardened flip-flop utilizing ST based SEM latch is presented. This flip-flop is significantly improves the performance and reliability compared to the existing flip-flops.

Tunnel field effect transistors (TFETs) have significantly steeper sub-threshold slope (24–30 mv/decade), as compared with the conventional metal–oxide–semiconductor field-effect transistors (MOSFETs), which have a sub-threshold slope of 60 mv/decade at room temperature. The steep sub-threshold slope of TFETs enables a much faster switching, making TFETs a better option than MOSFETs for low-voltage VLSI applications. The purpose of this paper is to present a novel hetero-junction TFET-based Schmitt triggers, which outperform the conventional complementary metal oxide semiconductor (CMOS) Schmitt triggers at low power supply voltage levels.

The conventional Schmitt trigger has been implemented with both MOSFETs and HTFETs for operation at a low-voltage level of 0.4 V and a target hysteresis width of 100 mV. Simulation results have indicated that the HTFET-based Schmitt trigger not only has significantly lower delays but also consumes lesser power as compared to the CMOS-based Schmitt trigger. The limitations of the conventional Schmitt trigger design have been analysed, and improved CMOS and CMOS–HTFET hybrid Schmitt trigger designs have been presented.

The conventional Schmitt trigger implemented with HTFETs has 99.9% lower propagation delay (29ps) and 41.2% lesser power requirement (4.7 nW) than the analogous CMOS Schmitt trigger, which has a delay of 36 ns and consumes 8 nW of power. An improved Schmitt trigger design has been proposed which has a transistor count of only six as compared to the eight transistors required in the conventional design. The proposed improved Schmitt trigger design, when implemented with only CMOS devices enable a reduction of power delay product (PDP) by 98.4% with respect to the CMOS conventional Schmitt trigger design. The proposed CMOS–HTFET hybrid Schmitt trigger further helps in decreasing the delay of the improved CMOS-only Schmitt trigger by 70% and PDP by 21%.

The unique advantage of very steep sub-threshold slope of HTFETs has been used to improve the performance of the conventional Schmitt trigger circuit. Novel CMOS-only and CMOS–HTFET hybrid improved Schmitt trigger designs have been proposed which requires lesser number of transistors (saving 70% chip area) for implementation and has significantly lower delays and power requirement than the conventional designs.

The paper aims to design of dual-mode boost converter with integrated low-voltage control circuit is introduced in this paper. The paper aims to discuss these issues.

The converter is operated either with LC filter or with charge pump circuit by the switch control. The control stage with error amplifier, comparator, and oscillator is designed with the supply voltage of 3.3 V and the operating frequency of 5.5 MHz. The compensator circuit exploits a pole compensation for a stable operation.

The simulation test in 0.35 μm CMOS process shows that the charge pump regulator and DC-DC boost converter are accurately controlled with the variation of number of stages and duty ratio. The output-voltage is obtained to be 6-15 V within the ripple ratio of 5 percent. Maximum power consumption is about 0.65 W.

This dual-mode is useful in the converter with a wide load-current variation. The advantage of the dual-mode converter is that it can be used in either high or low load current with a simple switch control. Furthermore, in charge pump regulator, there is no degradation of output voltage because of the feedback control circuit.

This paper aims to propose a low-power complementary MOS (CMOS) current sensor for control circuit in an integrated DC-DC buck converter.

The integrated DC-DC converter, which is composed of feedback control circuit and power block, is designed with 0.35-µm CMOS process. Current sensor in the control circuit is integrated with sense-FET and voltage-follower circuits to reduce power consumption and improve its sensing accuracy. In the current-sensing circuit, the size ratio of the power metal oxide semiconductor field effect transistor (MOSFET) to the sensing transistor (K) is 1,000, and a current-mirror is used for a voltage follower. N-channel MOS acts as a switching device in the current-sensing circuit, where the sensing FET is in parallel with the power MOSFET. The amplifier and comparator are designed to obtain a high gain and a fast transient time.

Experiment shows that the current sensor is operated with accuracy of more than 85 per cent, and the transient time of the error amplifier is controlled within 100 µs. The sensing current is in the range of a few hundred µA at a frequency of 0.6-2 MHz and an input voltage of 3-5 V. The output voltage is obtained as expected with the ripple ratio within 5 per cent.

The proposed current sensor in DC-DC converter provides an accurately sensed inductor current with a significant reduction in power consumption in the range of 0.2 mW. High-accuracy regulation is obtained using the proposed current sensor. As the sensor utilizes simple switch-type voltage follower and sense-FET, it can be widely applied to other low-power applications such as high-frequency oscillator and over-current protection circuit.

Details of Electrical and Electronic Apparatus and Applications in the Maintenance and Operation of Aircraft, Missiles and Space Vehicles. A completely new, compact airborne navigation computer has been designed by The Mareoni Co. to enable long‐range aircraft to navigate to within a few miles of any destination throughout the world—an automatic track guidance system that needs no aids or reference from ground stations.

This study aims to present a novel technique to localize the human position in a room, to manage people in a specified space.

In this study, a real-time human sensing detection and smart lighting control was designed within a single silicon core. The chip has been successfully realized within 1.5 mm² silicon area using TSMC 0.25 um process.

This chip can read the weak signal of pyroelectric infrared (PIR) sensor to find the position of human body in a dark room and then help control the smart lighting system for an intelligent surveillance system.

This chip presented the retriggering delay control to expand the LED lighting time infinitely to avoid lighting-off suddenly while users stay on a space. This function is very useful in a practical intelligent surveillance system that is mainly based on human detection to better reduce power dissipation and memory space.

In this chapter, the authors build on the voluntary turnover model posited by Allen, Bryant, and Vardaman (2010) with reference to turnover and retention within the United Kingdom. After providing important contextual material about the United Kingdom, the authors explore turnover drivers such as work precarity, as well as the effect of Brexit, which compounds the political and economic uncertainty engendered by the pandemic. Reflecting on the role of external shocks in precipitating withdrawal processes, the authors go on to examine the extent to which job embeddedness impacts on employee turnover, and how alternative opportunities in a UK context may shape the decisions people make to stay with or leave their organizations. Central to our argument is that human resource (HR) practices as perceived by employees play a critical role in shaping attitudes such that people wish to stay in the organization. Cultural values posited by Hofstede and others are likely to significantly impact the way in which employees respond to the HR practices they perceive. Hence, leaders and HR specialists in the United Kingdom need to deploy HR practices which speak to cultural values that stand out in that context, considering that the United Kingdom is characterized by relatively low levels of power distance, low uncertainty avoidance, high individualism and higher than average indulgence.

Taken together, the model provides an overview of key internal and external factors that influence employees’ attitudes at work, their withdrawal behaviors and the ensuing turnover at the organizational-level. The authors conclude by highlighting key research questions raised by the analysis of the model within a UK context, considering where empirical research will add to understanding about turnover and retention in the United Kingdom.