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Summary

12.1 INTRODUCTION

In electronics, an integrated circuit (also known as IC, microcircuit, microchip, silicon chip or chip) is a miniaturized electronic circuit (consisting mainly of semiconductor devices, as well as passive components) that is manufactured on the surface of a thin substrate of semiconductor material. A hybrid Integrated Circuit is a miniaturized electronic circuit constructed of individual semiconductor devices, as well as passive components, bonded to a substrate or circuit board. Integrated circuits are used in almost all electronic equipment and have revolutionized the world of electronics.

To a large extent, the demand for miniaturization was driven by the demands of the American Space Program. For some time, people had been thinking that it would be a good idea to be able to fabricate an entire circuit on a single piece of semiconductor. The first public discussion of this idea is credited to a British radar expert, Geoffrey William Arnold Dummer (1909–2002), in a paper presented in 1952. Jack Kilby's first prototype was a phase-shift oscillator comprising of five components on a piece of germanium, half an inch long and thinner than a toothpick. Although manufacturing techniques subsequently took different paths from those used by Kilby, yet he is considered as the pioneer in the area of IC fabrication.

ICs are polarized and every pin is unique in terms of both location and function. Most ICs use either a notch or a dot to indicate the pin numbers and its counting sequence. This is depicted in Figure 12.1.

12.2 IC: ADVANTAGES AND DISADVANTAGES

The main advantages of ICs over those made by interconnecting discrete components are as follows:

1. Extremely small size, i.e. thousands times smaller than discrete circuits. It is because of fabrication of various circuit elements on a single chip of semiconductor material.
2. Very small weight owing to miniaturized circuit.
3. Very low cost because of simultaneous production of hundreds of similar circuits on a small semiconductor wafer. Owing to mass production, IC costs as much as an individual transistor.
4. More reliable because of elimination of soldered joints and need for fewer interconnections.
5. Lower power consumption because of their smaller size.
6. Easy replacement as it is more economical to replace them than to repair them.
7. Increased operating speed because of absence of parasitic capacitance effect.
8. Close matching of components and temperature coefficients because of bulk production in batches.

Summary

INTRODUCTION

Modern international environmental law can be traced directly to international legal developments that took place in the second half of the nineteenth century. Thus, although the current form and structure of the subject emerged in the mid 1980s, a proper understanding of modern principles and rules requires a historic sense of earlier scientific, political and legal developments. International environmental law has evolved over four distinct periods, reflecting developments in scientific knowledge, the application of new technologies and an understanding of their impacts, changes in political consciousness and the changing structure of the international legal order and institutions.

A first period began with bilateral fisheries treaties in the nineteenth century, and concluded with the creation of the new international organisations in 1945. During this period, peoples and nations began to understand that the process of industrialisation and development required limitations on the exploitation of certain natural resources (flora and fauna) and the adoption of appropriate legal instruments. The second period commenced with the creation of the UN and culminated with the UN Conference on the Human Environment, held in Stockholm in June 1972. Over this period, a range of international organisations with competence in environmental matters was created, and legal instruments were adopted, at both the regional and the global levels, which addressed particular sources of pollution and the conservation of general and particular environmental resources, such as oil pollution, nuclear testing, wetlands, the marine environment and its living resources, the quality of freshwaters and the dumping of waste at sea. The third period ran from the 1972 Stockholm Conference and concluded with the UN Conference on Environment and Development (UNCED) in June 1992. During this period, the UN tried to put in place a system for coordinating responses to international environmental issues, regional and global conventions were adopted, and for the first time the production, consumption and international trade in certain products were banned at the global level. The fourth period was set in motion by UNCED, and may be characterised as a period of integration: when environmental concerns should, as a matter of international law and policy, be integrated into all activities and into the broader development agenda concerned with poverty eradication and improving human health.

Summary

It was that eccentric British soldier of fortune Col. Meinertzhagen, in his Birds of Arabia, who expressed the sentiment that prefaces should be kept short because few people ever read them. Accordingly, I would like to take a brief opportunity to express my gratitude to the people who offered encouragement and assistance during the preparation of this book. I would like to thank Adele Strauss Wolbarst, Robert Cnoops, Charmaine Slack, Sophia Skiordis, Caroline Mondel, Jill Keetley- Smith, Heather Edwards, Gail Arbeter, and the Lending Library at Boston Spa, England, for help while most of this manuscript was being prepared at the University of the Witwatersrand. For general encouragement while at Pahlavi (Shiraz) University and for providing assistance during the last turbulent and chaotic year of imperial rule in Iran, while the manuscript was being finished, I would like to thank Mark Gettner, Brian Coad, and Mumtaz Bokhari. When photographs or drawings have been taken directly from the original material, this is indicated by stating in the legend that it is from the original work. Most of the drawings have been redrawn to suit my tastes, and these drawings are indicated by stating that the work is after the original.

In some cases I have made drawings from photographs or have incorporated a number of drawings in one, in which case I state that the finished drawing is adapted from the original work or works. I have used the metric system in this book, and the fine-structural illustrations are expressed in micrometers (μm) and nanometers (nm).

Summary

10.1 INTRODUCTION

In Chapter 6, we derived various small-signal models of BJT, followed by detailed analysis of the BJT amplifiers for CE, CB and CC configurations. In designing such small-signal amplifier the main focus is on amplification linearity and magnitude of gain. Since signal voltage and current in the small-signal amplifier is restricted to small amplitude for maintaining linearity, their power handing capability or the power efficiency with which it delivers AC power to the load at the expense of DC power are of secondary concern. A voltage (current) amplifier provides voltage (current) amplification primarily to increase the applied input voltage (current). Thus, in general, these small-signal amplifiers are not capable of delivering large amount of power to a passive load. But most of the practical electronic amplifiers (starting from audio amplifier to switching power supply) require a final output stage capable of delivering large power to the load. Such amplifier/amplifying stage at the output stage of a practical amplifier circuit is known as power amplifier. It can be designed using BJTs, MOSFETs and various special semiconductor devices like thyristors. However, we will consider only BJTs while discussing the design of such amplifiers.

10.2 PERFORMANCE CHARACTERISTICS OF POWER AMPLIFIERS

The quality of power amplifiers is characterized by the following parameters:

• Power handling capability: The amplifier must be capable of delivering the required amount of power to the load in an efficient manner. This demands that the power dissipation in the transistors be as low as possible.
• High power conversion efficiency: Power conversion efficiency is another important figure of merit of a power amplifier defined as the ratio of AC power delivered to the load to the DC input power. It is expressed as,

We will calculate the power conversion efficiency η of different types of power amplifiers. A high value of η is desired as it utilizes less DC power to deliver same output AC power to the load.

• Low total harmonic distortion: Since a power amplifier deals with relatively large signals, the small-signal approximations and resultant linear equivalent circuit models are not applicable here due to the nonlinearities of the transistors while dealing with large signals. Even though power handling capability and high conversion efficiency are major design criteria in power amplifiers, linearity still remains an important criterion.

Summary

13.1 INTRODUCTION

Operational amplifier or OPAMP is one of the most important building blocks in all aspects of analog circuitry. It becomes the universal analog IC because of its wide range of application in analog signals processing. It can function as a line drive, comparator (one bit A/D), amplifier, level shifter, oscillator, filter, signal conditioner, actuator driver, current source, voltage source, and many other applications.

The OPAMP is a multistage two-input differential amplifier that is designed to be an almost ideal control device, specifically a voltage-controlled voltage source. Basically, it is an abstraction of ideal voltage amplifier with very high gain. We will employ the OPAMP to construct more complex circuits using its simple, abstract model. The equivalent circuit of OPAMP is shown in Figure 13.1.

The integrated circuit OPAMP usually consists of a cascade of three stages:

a) Input stage: May contain one or two differential amplifier stages
b) Intermediate stage: Emitter follower and DC level shifter.
c) Output stage: Driver stage (Class B amplifier)

Internally, the OPAMP itself is a moderately complicated circuit and its design is beyond the scope of this book. The heart of the OPAMP is its input stage acting as differential amplifier using BJT/MOSFET. This differential input stage gives the OPAMP its high input resistance and a high gain with very little noise. It also converts the differential input voltage to a single-ended output. A typical OPAMP also has a second stage similar to the first stage, which provides additional amplification and level shifts the output voltage to zero when both inputs are equal. OPAMPs may also have an output stage similar to the buffer, due to which OPAMP exhibits low output impedance.

Symbolic representation of the operational amplifier shown in Figure 13.2, suggests that it as a two-port device. The two ports are an input and an output port. A + V voltage (for example, 15 V) is applied at the ‘plus’ power port and a –V voltage (for example, −15 V) is applied at the ‘minus’ power port. An input voltage (the control) applied across the non-inverting and inverting input terminals of the OPAMP is amplified by a large amount and appears at the output port.

Summary

INTRODUCTION

Electronics, evolved from the word ‘electron’ (a sub-atomic particle carrying negative charge), is the branch of science and engineering dealing with the study, design and use of devices that depend on the conduction of electricity through vacuum, gas or semiconductor, contributed by the transport phenomenon of the electrons. Earlier, electronics or electronics engineering used to be considered as an integral part of electrical engineering. However, due to the tremendous growth of electronics and its unprecedented applications in various fields over the last few decades, it has evolved as a separate branch of engineering. In addition, due to its widespread application in almost all possible branches of engineering and science, acquiring basic understanding of electronics and fundamentals of electronic devices has become a common requirement for students of all engineering disciplines.

Before we discuss the details of the preliminary concepts required to understand the basic ideas of electronics, let us have a look at the chronological growth of modern electronics:

Summary

INTRODUCTION

This chapter describes the general principles and rules of international environmental law as reflected in treaties, binding acts of international organisations, state practice, judicial decisions and soft law commitments. The existence and applicability of ‘principles of international environmental law’ were confirmed by the arbitral tribunal in the Iron Rhine case. Such principles are general in the sense that they are potentially applicable to all members of the international community across the range of activities that they carry out or authorise and in respect of the protection of all aspects of the environment. From the large body of international agreements and other acts it is possible to discern general rules and principles that have broad, if not necessarily universal, support and are frequently endorsed in practice. These are:

Summary

INTRODUCTION

The invention of various semiconductor devices and the chronological growth in the field of microelectronics in electronics industry is the backbone of most of the modern electrical/electronic and communication gadgets that have dramatically changed human life, leading to a new technology-driven society. One of the most remarkable breakthroughs to drive technology in the last few decades is the invention of transistor, a three terminal device that is extremely useful and almost an integral part of any analog or digital circuit. The first version of transistor was invented by Dr William Shockley and his co-workers Walter H Brattain and John Bardeen in Bell Lab, USA in 1947. Owing to various operational advantages like low power requirements, high efficiency, etc., coupled with its ultra-compact size, the transistor became very popular since its invention and replaced the previously used vacuum tube-based systems. Over time, the first transistor invented by Shockley et al (point-contact transistor) went through several rounds of modification, resulting in various new variants of the transistor, which include Bipolar Junction Transistor (BJT), Field Effect Transistor (FET), Metal Oxide Semiconductor Field Effect Transistor (MOSFET), etc.

In this chapter, we will discuss the construction of a transistor, basic principle of operation and its two most important applications, namely amplification and switching, in detail. Advanced concept regarding transistor operation and various other functionalities will be discussed in subsequent chapters.

BJT: CONSTRUCTION AND TERMINALS

A Bipolar Junction Transistor, popularly known as BJT, is a three-terminal semiconductor device with two junctions between them. As shown in Figure 4.1(a), the structure of a transistor resembles a sandwich in which a very narrow and lightly doped p-region is sandwiched between two n-regions. Such a transistor is named as n-p-n transistor. A complementary structure of Figure 4.1(a), as shown in Figure 4.1(b), consists of an n-region sandwiched between two p-regions, resulting in a p-n-p transistor. The term ‘bipolar’ in BJT signifies the presence of two different types of carriers, electron and hole, and the resultant current is the combined contribution of both the carriers. As indicated in Figure 4.1, the three regions of the transistor are named as emitter (E), base (B) and collector (C).

Summary

Just as new transnational strategic imperatives put demands on MNEs’ existing organizational capabilities, so have evolving transnational organization models defined new managerial tasks for those operating within them. In this chapter, we examine the changing roles and responsibilities of three typical management groups that find themselves at the decision-making table in today's transnational organizations: the global business manager, the worldwide functional manager, and the national subsidiary manager. Although different organizations may define the key roles differently (bringing global account managers or regional executives to the table, for example), the main challenge facing all MNEs is to allocate their major strategic tasks and organizational roles among key management groups. Just as important is the subsequent need to give each of those groups the appropriate legitimacy and influence within the organization's ongoing decision-making process. The focus of this chapter is to provide an overview of the new roles and responsibilities of these key executives before concluding with a review of the role of top management in integrating their diverse interests and perspectives, and engaging them around a common direction.

As earlier chapters have made clear, the twenty-first century MNE is markedly different from its twentieth century predecessors. It has been transformed by an environment in which multiple, often conflicting forces accelerate simultaneously. The globalization of markets, the acceleration of product and technology life cycles, the assertion of national governments’ demands, and, above all, the intensification of global competition have created an environment of complexity, diversity, and change for most of today's MNEs.

As we have seen, the ability of a company to compete based on a single dominant competitive advantage has morphed into a need to develop multiple strategic assets: global-scale efficiency and competitiveness, national responsiveness and flexibility, and worldwide innovation and learning capabilities. In turn, these new strategic demands have put pressure on existing organization structures and management processes. Traditional hierarchical structures, with their emphasis on either/or choices, have evolved toward organizational forms that we have described as transnationals. Such organizations are characterized by their abilities to manage integrated networks of assets and resources, multidimensional management perspectives and capabilities, and flexible coordinative processes.

Summary

INTRODUCTION

A wide range of actors participate in those aspects of the international legal order which address environmental issues, including the negotiation, implementation and enforcement of international environmental agreements. Apart from the state delegations that play a central role, a visitor to climate change or other negotiations would find international organisations and non-state actors actively involved. International environmental law is characterised by this phenomenon that, with the possible exception of the human rights field, renders it unique. Various reasons explain this state of affairs. States are involved because they are still the pre-eminent international legal persons. International organisations participate because they have been created by states to address particular environmental or related issues. Of the various non-state participants, the scientific community is involved because, to a great extent, international environmental law is driven by scientific considerations; the corporate sector is involved because of the significant implications which decisions taken at the global level have even for individual companies; and environmental non-governmental organisations (NGOs) are involved because they advocate for concerns often not pursued by states and see the need for active participation at the international level as the lines dividing local, national and global issues disintegrate. The participation of non-state actors in international environmental law has an established history, and is widely accepted.

The various actors have different roles and functions, both as subjects and as objects of international environmental law, including: participating in the lawmaking process; monitoring implementation, including reporting; and ensuring implementation and enforcement of obligations. The role of each actor turns upon its international legal personality and upon the rights and obligations granted to it by general international law and the rules established by particular treaties and other rules. The Rio Declaration and Agenda 21, as well as an increasing number of international environmental agreements, confirm the central role of international organisations and non-state actors in all aspects of the international legal process.

Summary

4.1 INTRODUCTION

4.2 BJT: CONSTRUCTION AND TERMINALS

Summary

This chapter shifts our focus from the internal forces that drive companies to expand to the larger, external, international environment in which they must operate. In particular, we consider three sets of macro forces that drive, constrain, and shape the industries in which entities compete globally. First, we examine the pressures – mostly economic – that drive companies in many industries to integrate and coordinate their activities across national boundaries to capture scale economies or other sources of competitive advantage. Second, we explore the forces – often social and political – that shape other industries and examine how they can drive MNEs to disaggregate their operations and activities to respond to national, regional, and local needs and demands. And third, we examine how, in an information-based, knowledge-intensive economy, players in a growing number of industries must adapt to opportunities or threats wherever they occur in the world by developing innovative responses and initiatives that they diffuse rapidly and globally to capture a knowledge-based competitive advantage.

Continual change in the international business environment has always characterized the task facing MNE managers, and the situation at the end of the second decade of the twenty-first century is no different. Important shifts in political, social, economic, and technological forces have combined to create management challenges for today's MNEs that differ fundamentally from those facing companies just a couple of decades ago. Yet despite intense study by academics, consultants, and practicing managers, both the nature of the various external forces and their strategic and organizational implications are still widely disputed.

When Levitt's classic Harvard Business Review article, “The globalization of markets,” was first published, his ideas provoked widespread debate. In Levitt's view, technological, social, and economic trends were combining to create a unified world marketplace that was driving companies to develop globally standardized products that would enable them to capture global economies. Critics, however, claimed that Levitt presented only one side of the story. They suggested that, like many managers, he had become so focused on the forces for globalization that he was blind to their limitations and equally powerful countervailing forces.

Summary

The second edition of Principles of International Environmental Law indicates that the legal aspects of international environmental issues are of growing intellectual and political interest, and that they have moved beyond the situation I described nearly ten years ago as reflecting ‘an early phase of development’. It is apparent from the new material which this edition treats – new conventions, new secondary instruments, new (or newly recognised) norms of customary law, and a raft of new judicial decisions – that international environmental law is now well established and is a central part of the international legal order. It is also clear that international environmental law has reached new levels of complexity, in particular as it has become increasingly integrated into other social objectives and subject areas, particularly in the economic field. The burgeoning case law, and the increased involvement of practitioners, suggests that it can no longer be said that international environmental law is, as a branch of general public international law, at an early stage of practical development.

Like the first edition, this edition (together with the accompanying volume of international documents for students) is intended to provide a comprehensive overview of those rules of public international law which have as their object the protection of the environment. Those rules have become more numerous and complex, but also more accessible: the advent of the Internet often means that material which was previously difficult to track down – for example, information as to the status, signature and ratification of treaties, and acts and decisions of Conferences of the Parties and subsidiary bodies – is now relatively easy to obtain. But the Internet also increases the danger of becoming overwhelmed by the sheer quantity of material that is now available, a risk which is exacerbated by the very extensive (and growing) secondary literature which is produced every year, only a small proportion of which may really be said to indicate real insights into new developments. This background necessarily means that what is gained on breadth may be lost – at least in some areas – on depth. This comprehensive account cannot address all of the details that now dominate specific areas – trade, fisheries and climate change spring immediately to mind – and the reader will need to refer to more detailed accounts of particular sectors, and the websites of various conventions, to obtain many of the details.

Summary

P-N JUNCTION

All modern semiconductor devices and integrated circuits (IC), which are the backbone of modern day electronics, contain at least one junction between p-type and n-type semiconductor, commonly known as p-n junction. This p-n junction is the most fundamental semiconductor device as all other devices like various types of transistors (Bipolar Junction Transistor, Field Effect Transistor, Metal Oxide Semiconductor Field Effect Transistor, etc.) require p-n junctions of various configurations, which will be discussed in subsequent chapters. Various analog and digital operations and performance like rectification, amplification, switching, logic operations require this fundamental semiconductor device. In this chapter, we will discuss various issues related to the p-n junction followed by application of such junction diodes, called p-n junction diodes, for various operations.

In chapter 2, we have been familiar with different types of semiconductors, classified in different aspects. We recall p- and n-type semiconductor, which are realized by doping an intrinsic semiconductor with different type of impurities to obtain large number of free carriers in the form of holes in p-type semiconductor and electrons in n-type semiconductor, respectively. However, these n-type and p-type semiconductors having electrons and holes in abundance are electrically neutral, as they are neutralized by the impurity ions which have created them. To be more specific, electrons are neutralized by associated donor ions, each of which has equal (opposite in sign) amount of charge as that of each electron, and holes are neutralized by acceptors ions, each of which has equal (opposite in sign) amount of charge as that of a hole, ensuring a charge neutrality. This is clearly shown in Figure 3.1. However, if we consider a semiconductor whose two sides are differently doped with acceptor and donor impurities, their effect is not like two isolated pieces of p- and n- type semiconductor due to the transport phenomena of the mobile charge carriers. Such a device is known as p-n junction and needs to be discussed in detail. It is the most fundamental semiconductor device and is the backbone of modern day electronics.

A p-n junction is formed from a single crystal intrinsic semiconductor in which one side is doped with acceptor impurity, i.e. trivalent atoms (p-region), and the other side is doped with donor impurity, i.e. pentavalent atoms (n-region).

Summary

Introduction

What do we mean by intelligence? This is not an easy question to answer in a philosophical sense. However, if we are willing to accept a subjective answer, then we can start by declaring that humans are intelligent. This still leaves a question mark over many other species on the Earth. If we are willing to be more specific still, then we can consider only intelligence that is capable of communicating signals across space. At present this is the only type of extraterrestrial intelligence we can hope to discover. So, for the purposes of this chapter, when we refer to intelligent life it should be understood that we mean life that can engage in interstellar communication. (In this pragmatic usage, humans have been ‘intelligent’ for only a few decades and Newton, Darwin and many other great scientists of the past don't actually qualify as having been intelligent life.)

With our pragmatic interpretation of intelligence, SETI, the Search for Extraterrestrial Intelligence, is a well-defined problem: we must search for signals from life elsewhere in the Universe. Given our current technology, only signals transmitted as electromagnetic radiation are detectable, though there is also the possibility that we may be visited by an alien spacecraft or encounter a robotic messenger device. A plausible example of the latter would be an autonomous interstellar probe, probably with a high level of artificial intelligence, loaded with information that its home civilization wished to share. Such a device is known as a Bracewell probe, after the Australian scientist Ronald Bracewell (1921–2007) who proposed the concept in 1960. A Bracewell probe could be intended to be encountered physically, or a short-range (less than interstellar) communications strategy could be used, but in either case it would need to travel at least decades and maybe far longer to reach us. Seeking signs of alien artifacts, ranging from small probes to colossal works of astroengineering, is referred to as SETA (Search for Extraterrestrial Artifacts). We will focus here on searching for signals originating from the alien's home planet, and thus on SETI rather than SETA.

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7 - Field-Effect Transistors

Chapter 12 - Integrated Circuits

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2 - History

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Dedication

Part I - The Strategic Imperatives

Preface to the First Edition

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Chapter 10 - Power Amplifiers

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Chapter 13 - Operational Amplifier

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1 - Introduction to Electronics: Basic Ideas

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List of Figures

6 - General Principles and Rules

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4 - Bipolar Junction Transistor

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7 - Building New Management Capabilities: Key to Effective Implementation

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3 - Governance: States, International Organisations and Non-State Actors

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Chapter 4 - Bipolar Junction Transistor

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2 - Understanding the International Context: Responding to Conflicting Environmental Forces

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Preface and Acknowledgements to the Second Edition

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3 - P-N Junction and P-N Junction Diode

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Chapter 9 - Extraterrestrial INtelligence

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Table of Treaties and Other International Instruments

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