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This article critically examines the relationship between self-esteem and criminal social identity in violent offenders, offering a novel rehabilitative framework within the Indian penal system. Despite global recognition of identity reformation as integral to offender rehabilitation, India has yet to integrate these psychological dimensions into correctional strategies. This research, conducted at Sabarmati Central Prison, Ahmedabad, applies structured therapeutic interventions to assess shifts in self-esteem and criminal social identity among 70 violent offenders, measured pre- and post-intervention. Criminal social identity reflects the internalization of criminality as a defining role, while self-esteem denotes an individual’s perceived legitimacy within social norms. The findings underscore the formative influence of environmental, familial and sociocultural factors, revealing a significant interplay between self-concept and criminal behaviour. Statistically significant improvements post-intervention demonstrate the potential for identity reconstruction as a rehabilitative tool. This analysis challenges punitive correctional models, advocating for evidence-based, human-centred interventions that prioritize psychological rehabilitation. By offering a culturally contextualized approach, this article contributes to contemporary debates on criminal justice reform, providing a blueprint for integrating psychological insights into correctional policy in India and beyond.

Providing in-depth coverage and comprehensive discussion on essential concepts of electronics engineering, this textbook begins with detailed explanation of classification of semiconductors, transport phenomena in semiconductor and Junction diodes. It covers circuit modeling techniques for bipolar junction transistors, used in designing amplifiers. The textbook discusses design construction and operation principle for junction gate field-effect transistor, silicon controlled rectifier and operational amplifier. Two separate chapters on Introduction to Communication Systems and Digital Electronics covers topics including modulation techniques, logic circuits, De Morgan's theorem and digital circuits. Applications of oscillators, silicon controlled rectifier and operational amplifier are covered in detail. Pedagogical features including solved problems, multiple choice questions and unsolved exercises are interspersed throughout the textbook for better understating of concepts. This text is the ideal resource for first year undergraduate engineering students taking an introductory, single-semester course in fundamentals of electronics engineering/principles of electronics engineering.

The COVID-19 pandemic and lockdown pushed several groups of traders to rely on cryptocurrency as one of the chosen tools for commercial transactions. India is no exception. Because of its notorious misuses by criminal gangs, the Reserve Bank of India (RBI) declared cryptocurrency as derecognized. Consequently, the Indian parliament also created a draft bill titled Banning of Cryptocurrency & Regulation of Official Digital Currency Bill, 2019 (the Bill), which not only derecognizes the currency or the use of it for any commercial purposes, it also makes the investors, exchanges and agencies dealing with cryptocurrency criminally liable. Later, the Supreme Court of India in 2020 set aside the above-mentioned RBI guidelines banning cryptocurrency. But this has not nullified or suggested any amendment for the Bill. This article argues that due to this legal confusion, cryptocurrency investors, traders, exchanges and agencies, etc. have become guardian-less victims who may not be eligible to claim basic rights of victims as has been established by the United Nations Declaration of Basic Principles of Justice for Victims of Crime and Abuse of Power. In such a legal tangle, it is necessary to analyse the issues from cyber-victimological perspectives for providing functional suggestions for restitution of justice.

Summary

3.1 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.

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

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

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

4.1 INTRODUCTION

4.2 BJT: CONSTRUCTION AND TERMINALS

Summary

P-N JUNCTION

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

In Chapter 4, we discussed the basic construction, characteristics, various modes and principle of operation of bipolar junction transistor (BJT) in detail. Subsequently, in Chapter 5, we dealt with biasing techniques of the transistor in an elaborate manner. In addition, we understood the fundamental concept of BJT acting as an amplifier in a qualitative manner. While biasing a transistor our main goal is to fix a proper operating point, also known as Q point, based on the specific applications. This is achieved by proper choice of the bias resistor and DC voltages. Once this Q-point is finalized, we apply the AC signal in the input side of the biased transistor circuit. Thus, complete analysis of an amplifier consists of DC analysis followed by an AC analysis. In this chapter, we will focus on the AC analysis of the BJT circuits in an elaborate manner with special emphasis on design of the BJT-based linear amplifiers. One important ingredient in the AC analysis and design of linear amplifiers is to replace the BJT with proper equivalent circuits. Such replacement of BJTs with equivalent circuits, known as ‘modeling’ of the BJT, is applicable under small signal approximations. This assumes the amplitude of the applied AC signal is small enough to consider that BJT is essentially operated in active region and its characteristics can be approximated by linear relations. Such linear relations between input and output signals of the BJT allow superposition theorem applicable in BJT circuits and we can obtain the total response of the BJT circuit by separately determining the response due to i) DC sources alone (called biasing), and ii) AC sources. Figure 6.1 shows a schematic diagram of an electronic circuit driven by both DC and AC input. While the purpose of the DC input is to ensure that the device operates in the desired region of operation, i.e. bias the device properly, AC input provides the required functionality like amplification, switching, etc. By applying the small-signal models of the device, thereby linearizing their performance, we apply the superposition theorem to obtain the overall response of the circuit by separately obtaining the individual responses due to DC input and AC input, as shown in Figure 6.1.

Summary

INTRODUCTION

IC: ADVANTAGES AND DISADVANTAGES

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

Summary

15.1 INTRODUCTION

In previous chapters, we dealt with various electronic devices (diode, BJT, FET, etc.) that have been used to design various electronic circuits like rectifier, various kind of amplifiers, oscillators, etc. For all these electronic circuits, the input and or output signals can take any value within a practical range; such signals are known as ‘analog’ signal. Electronic circuits and systems dealing with such analog signals are commonly known as analog circuits. Even though all practical signals are analog in nature, various practical applications and processing of these analog signal require certain sort of quantization and discretization. For instance, while measuring voltage/current using an analog meter, we rely on the deflection of the needle on a properly calibrated scale. Using such analog meter, we can measure any practical voltage/current. On the other hand, while measuring same voltage or current using a digits meter we can get only certain discrete values based on the number of digits in the display panel. However, if adequate numbers of display digits are used, it will provide very accurate result!

In this chapter, we will introduce the basic concepts and circuits dealing with digital signal, a signal that can take only a finite number of values.

Figure 15.1(a) and (b) show an analog and digital signal plotted against time(t). As discussed previously, analog signal can take any value within a range, while for a digital signal only a few restricted ranges of amplitudes are allowed. The most common digital signals are binary signal that takes amplitude either high (represented as ‘1’) or low (represented as ‘0’). The circuit that deals with digital signals is commonly known as digital circuit. Most of the modern electronic systems like computer, memory circuits, microprocessors and various electronic gadgets like cell phone, iPad, laptop, etc. are high-end examples of digital circuits.

The objective of this chapter is to learn the features and operations of fundamental digital logic circuits, which are the backbone of the modern digital computers.

15.2 DIFFERENT NUMBER SYSTEMS

To have a clear idea on how arithmetic and logical operations are executed in digital systems, we need to be familiar with various schemes of representation of number in digital systems. From our childhood and school days, we have been familiar with decimal number system, which consists of 10 digits, ranging from 0 to 9.

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Reconstructing the Self: Assessing Self-Esteem and Criminal Social Identity in Violent Offenders for Rehabilitation in the Indian Penal System

Basic Electronics

Legal Challenges to Cryptocurrency and its Guardian-Less Victims in India: A Critical Victimological Analysis

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

Summary

7 - Field-Effect Transistors

Chapter 12 - Integrated Circuits

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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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4 - Bipolar Junction Transistor

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Chapter 4 - Bipolar Junction Transistor

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

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9 - Oscillators and Multivibrators

Frontmatter

6 - Modelling of BJT and Design of Amplifiers

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Dedication

12 - Integrated Circuits

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Contents

Acknowledgements

Chapter 15 - Introduction to Digital Logic Circuits

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Basic Electronics

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