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Article
Publication date: 1 January 1980

John Monk

Microelectronics and in particular microprocessors and the microcomputers of which they are a part, are capable of performing complex data processing tasks. The costs of…

Abstract

Microelectronics and in particular microprocessors and the microcomputers of which they are a part, are capable of performing complex data processing tasks. The costs of these electronic systems has fallen to a level where they can be considered by a designer to be a part of industrial, office and even domestic goods competing with older mechanical, electrical and electronic techniques. These electronic systems have also made economically feasible new products which were previously too expensive using the alternative methods of operation. The rapid rate of development and the consequent reductions in prices of microelectronics and the products that use it particularly in the sphere of automation, on the shop floor and in the office has given academics, researchers, politicians and trade unionists a cause for concern. The worries are that new tools for production incorporating microelectronics will displace labour and that furthermore many new products that incorporate microelectronics will require fewer people to assemble smaller numbers of standardised components. At the same time many industrialists see opportunities for new products helping to raise the standard of living and employing people in their production. There is therefore a balance between employment in the production of new products and the displacement of labour as products and labour intensive production processes are made obsolescent. The debate is whether the advent of microelectronics will significantly increase unemployment or not and if it does, what the effects on society will be. However, if the advantages of microelectronics are merely temporary then the changes that have been seen so far may be the full extent of the revolution that is being presaged. This paper explains how microelectronic components are made and examines the constraints on their development to show that even though current components have not achieved their full influence there is still likely to be considerable increases in the capabilities of microelectronics, microcomputers and the electronic systems that incorporate them.

Details

International Journal of Social Economics, vol. 7 no. 1
Type: Research Article
ISSN: 0306-8293

Article
Publication date: 1 March 1979

D. Weinerth

The approach to reduce the costs of electronic circuits will be the transition of LSI‐circuits to VLSI‐circuits, introducing another order of magnitude to the complexity…

Abstract

The approach to reduce the costs of electronic circuits will be the transition of LSI‐circuits to VLSI‐circuits, introducing another order of magnitude to the complexity and density of these circuits. The influence of this will be similar to the transition of discrete transistors to integrated circuits. VLSI‐circuits are, in general, digital circuits and therefore the passive components used in analogue circuits will be used in smaller quantities, just as the discrete transistors will change from small signal to power. Sensors and display units as liquid crystals will gain importance and need to be interconnected in an economic way. Competing with printed circuit boards are hybrid circuits, but these have not yet found general application due to the high innovation rate of integrated circuits. However, special applications as high frequency circuits are cost effective. A cost breakdown of electronic equipment shows that due to the introduction of LSI and VLSI circuits the relative costs of PCB's are rather high and that economics will force the introduction of new technolgies to achieve the correct cost balance.

Details

Circuit World, vol. 5 no. 4
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 5 May 2015

Pradeep Kumar Rathore, Brishbhan Singh Panwar and Jamil Akhtar

The present paper aims to propose a basic current mirror-sensing circuit as an alternative to the traditional Wheatstone bridge circuit for the design and development of…

Abstract

Purpose

The present paper aims to propose a basic current mirror-sensing circuit as an alternative to the traditional Wheatstone bridge circuit for the design and development of high-sensitivity complementary metal oxide semiconductor (CMOS)–microelectromechanical systems (MEMS)-integrated pressure sensors.

Design/methodology/approach

This paper investigates a novel current mirror-sensing-based CMOS–MEMS-integrated pressure-sensing structure based on the piezoresistive effect in metal oxide field effect transistor (MOSFET). A resistive loaded n-channel MOSFET-based current mirror pressure-sensing circuitry has been designed using 5-μm CMOS technology. The pressure-sensing structure consists of three identical 10-μm-long and 50-μm-wide n-channel MOSFETs connected in current mirror configuration, with its input transistor as a reference MOSFET and output transistors are the pressure-sensing MOSFETs embedded at the centre and near the fixed edge of a silicon diaphragm measuring 100 × 100 × 2.5 μm. This arrangement of MOSFETs enables the sensor to sense tensile and compressive stresses, developed in the diaphragm under externally applied pressure, with respect to the input reference transistor of the mirror circuit. An analytical model describing the complete behaviour of the integrated pressure sensor has been described. The simulation results of the pressure sensor show high pressure sensitivity and a good agreement with the theoretical model has been observed. A five mask level process flow for the fabrication of the current mirror-sensing-based pressure sensor has also been described. An n-channel MOSFET with aluminium gate was fabricated to verify the fabrication process and obtain its electrical characteristics using process and device simulation software. In addition, an aluminium gate metal-oxide semiconductor (MOS) capacitor was fabricated on a two-inch p-type silicon wafer and its CV characteristic curve was also measured experimentally. Finally, the paper presents a comparative study between the current mirror pressure-sensing circuit with the traditional Wheatstone bridge.

Findings

The simulated sensitivities of the pressure-sensing MOSFETs of the current mirror-integrated pressure sensor have been found to be approximately 375 and 410 mV/MPa with respect to the reference transistor, and approximately 785 mV/MPa with respect to each other. The highest pressure sensitivities of a quarter, half and full Wheatstone bridge circuits were found to be approximately 183, 366 and 738 mV/MPa, respectively. These results clearly show that the current mirror pressure-sensing circuit is comparable and better than the traditional Wheatstone bridge circuits.

Originality/value

The concept of using a basic current mirror circuit for sensing tensile and compressive stresses developed in micro-mechanical structures is new, fully compatible to standard CMOS processes and has a promising application in the development of miniaturized integrated micro-sensors and sensor arrays for automobile, medical and industrial applications.

Article
Publication date: 3 April 2018

Hyung-won Kim, Hyeim Jeong, Junho Yu, Chan-Soo Lee and Nam-Soo Kim

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

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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.

Originality/value

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

Microelectronics International, vol. 35 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 18 September 2007

G. Tessier, M. Bardoux, C. Filloy, C. Boué and D. Fournier

Heating is a major cause of failure in integrated circuits. The authors have designed thermoreflectance‐based systems operating at various wavelengths in order to obtain…

Abstract

Purpose

Heating is a major cause of failure in integrated circuits. The authors have designed thermoreflectance‐based systems operating at various wavelengths in order to obtain temperature images. This paper aims to explore the possibilities of each wavelength range and detail the charge coupled device (CCD)‐based thermal imaging tools dedicated to the high‐resolution inspection of integrated circuits.

Design/methodology/approach

Thermoreflectance is a non‐contact optical method using the local reflectivity variations induced by heating to infer temperature mappings, and can be conducted at virtually any wavelength, giving access to different types of information. In the visible, the technique is now well established. It can probe temperatures through several micrometers of transparent encapsulation layers, with sub‐μm spatial resolution and 100 mK thermal resolution.

Findings

In the ultraviolet range, dielectric encapsulation layers are opaque and thermoreflectance gives access to the surface temperature. In the near infrared, thermoreflectance is an interesting solution to examine chips turned upside down, since these wavelengths can penetrate through silicon substrates and give access to the temperature of the active layers themselves.

Research limitations/implications

The authors show that the illumination wavelength of thermoreflectance should be chosen with care depending on the region of the integrated circuit (surface, above, or below the substrate) to be investigated.

Practical implications

This set of versatile and sensitive tools makes thermoreflectance an interesting tool for the semiconductor industry, either during prototyping or as a characterization tool after fabrication.

Originality/value

The CCD‐based thermoreflectance approach adopted here allows fast, non‐contact, high‐resolution thermal imaging of integrated circuits.

Details

Sensor Review, vol. 27 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 2 August 2011

Franciszek Balik

The purpose of this paper is to present a new method of optimization of electronic integrated circuits (IC) with imbedded passive modules (PM). The reported method…

Abstract

Purpose

The purpose of this paper is to present a new method of optimization of electronic integrated circuits (IC) with imbedded passive modules (PM). The reported method constitutes an attempt to streamline the optimization process in the AC electrical model stage of the RF Microsystems design.

Design/methodology/approach

In this method, the PM are described in symbolic form while the IC blocks remain described numerically. Whole PM can be represented as some sequence of expressions containing crucial model parameters, nominal and parasitic, which are first precompiled and next, merged automatically with the main program.

Findings

The input data can be updated online according to the user's desiderata. Further, the system offers the possibility to optimize PM in diverse circumstances as well as using different technologies, and including parasitic effects.

Originality/value

Usage of the semi‐symbolic method for IC with embedded PM optimization based on large‐change sensitivity AC analysis method, which appears to be a very efficient and flexible approach to solving such problems.

Details

Microelectronics International, vol. 28 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 7 November 2022

Rajamohana Kuselan and Venkatesan Sundharajan

This study aims to extend the driving range by on-board charging with use of photovoltaic (PV) source, avoiding the dependency on the grid supply and energy storage system…

Abstract

Purpose

This study aims to extend the driving range by on-board charging with use of photovoltaic (PV) source, avoiding the dependency on the grid supply and energy storage system in addition to that reduce the conversion complexity influenced on converter section of electric vehicle (EV) system.

Design/methodology/approach

This paper proposed a PV fed integrated converter topology called integrated single-input multi-output (I-SIMO) converter with enriched error tolerant fuzzy logic controller (EET-FLC) based control technique to regulate the speed of brushless direct current motor drive. I-SIMO converter provides both direct current (DC) and alternating current (AC) outputs from a single DC input source depending on the operation mode. It comprises two modes of operation, act as DC–DC converter in vehicle standby mode and DC–AC converter in vehicles driving mode.

Findings

The use of PV panels in the vehicle helps to reduce dependence of grid supply as well as vehicle’s batteries. The proposed topology has to remove the multiple power conversion stages in EV system, reduce components count and provide dual outputs for enhancement of performance of EV system.

Originality/value

The proposed topology leads to reduction of switching losses and stresses across the components of the converter and provides reduction in system complexity and overall expenditure. So, it enhances the converter reliability and also improves the efficiency. The converter provides ripple-free output voltage under dynamic load condition. The performance of EET-FLC is studied by taking various performance measures such as rise time, peak time, settling time and peak overshoot and compared with conventional control designs.

Article
Publication date: 31 January 2020

Wolfgang Mathis

This work is intended to historically commemorate the one hundredth anniversary of the invention of a new type of electronic circuit, referred to in 1919 by Abraham and…

Abstract

Purpose

This work is intended to historically commemorate the one hundredth anniversary of the invention of a new type of electronic circuit, referred to in 1919 by Abraham and Bloch as a multivibrator and by Eccles and Jordan as a trigger relay (later known as a flip-flop).

Design/methodology/approach

The author also considers the circuit-technical side of this new type of circuit, considering the technological change as well as the mathematical concepts developed in the context of the analysis of the circuit.

Findings

The multivibrator resulted in a “circuit shape” which became one of the most applied nonlinear circuits in electronics. It is shown that at the beginning the multivibrator as well as the flip-flop circuits were used because their interesting properties in the frequency domain.

Originality/value

Therefore, it is a very interesting subject to consider the history of the multivibrator as electronic circuits in different technologies including tube, transistors and integrated circuits as well as the mathematical theory based on the concept from electrical circuit theory.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 39 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 21 July 2022

Fatima Iftikhar, Suleman Anis, Umar Bin Asad, Shagufta Riaz, Muntaha Rafiq and Salman Naeem

Carpal tunnel syndrome (CTS) is a hand disease caused by the pressing of the median nerve present in the palmar side of the wrist. It causes severe pain in the wrist…

Abstract

Purpose

Carpal tunnel syndrome (CTS) is a hand disease caused by the pressing of the median nerve present in the palmar side of the wrist. It causes severe pain in the wrist, triggering disturbance during sleep. Different products like splints, braces and gloves are available in the market to alleviate this disease but there was still a need to improve the wearability, comfort and cost of the product. This study was about designing a comfortable and cost-effective wearable system for mild-to-moderate CTS. Transcutaneous electrical nerve stimulation (TENS) therapy has been used to reduce the pain in the wrist.

Design/methodology/approach

After simulation by using Proteus software (which allowed the researchers to draw and simulate electrical circuits using ISIS, ARES and PCB design tools virtually), the circuit with optimum frequency, i.e. 33 Hz was selected, and the circuit was developed on a printed circuit board (PCB). The developed circuit was integrated successfully into the half glove structure.

Findings

The developed product had good thermophysiological comfort and hand properties as compared to the commercially available product of the same kind. In vivo testing (It involves the testing with living subjects like animals, plants or human beings) was performed which resulted in 85% confirmed viability of the product against CTS. A glove with an integrated circuit was developed successfully to accommodate various sizes without any sex specifications in a cost-effective way to mitigate the issue of CTS.

Research limitations/implications

Industrial workers, individuals frequently using their hands or those diagnosed with CTS may wish to use this product as therapy. The attention could not be paid to the aesthetic or visual appeal of the developed product.

Originality/value

A very comfortable glove with integrated TENS electrodes was developed successfully to accommodate various sizes without any sex specifications in a cost-effective way to mitigate the issues of CTS.

Details

Research Journal of Textile and Apparel, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 1 November 1996

K. Kumar

Data for reliability prediction of integrated circuits is obtained either from well designed accelerated life tests or from MIL‐HDBK‐217E. Although a number of researchers…

343

Abstract

Data for reliability prediction of integrated circuits is obtained either from well designed accelerated life tests or from MIL‐HDBK‐217E. Although a number of researchers have questioned the validity of prediction based on the data derived from this standard, it continues to remain the main source of failure data. Manufacturers normally specify chip reliability by a single failure rate, which is known to be incorrect. In a chosen reliability test, devices fail with different failure mechanisms characterized by their associated Arrhenius parameters. An overall failure rate for an integrated circuit is obtained by adding the individual failure rates. This amounts to ignoring the terms containing the product of probability of failure for different failure mechanisms. These terms can be ignored only if different failure mechanisms are mutually exclusive. Highlights this point, by using the published data and shows that a significant improvement is obtained by including the product terms. Demonstrates the idea of dropping the product term is sterile from theoretical as well as practical points of view and as such must be included. The chosen model and the example considered are for illustration only and the conclusion arrived at is not affected by the inherent uncertainties buried under the prediction process and associated tools. In this case it is equivalent to an improvement by 6 FITS. This approach is likely to have a meaningful impact on the economics of reliability prediction.

Details

International Journal of Quality & Reliability Management, vol. 13 no. 8
Type: Research Article
ISSN: 0265-671X

Keywords

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