BASIC ELECTRONICS BHARGAVA PDF
Basic Electronics and Linear Circuits. By N. N. Bhargava, N. N. Bhargava S. C. Gupta D. C. Kulshreshtha. About this book · Shop for Books on Google Play. N.N. Bhargava- Basic Electronics and Linear Circuits - Ebook download as PDF File .pdf), Text File .txt) or read book online. N.N. Bhargava- Basic Electronics. Basic Electronics and Linear Circuits_N. N. Bhargava, D. C. Kulshreshtha and S. C. Gupta - Download as PDF File .pdf), Text File .txt) or read online. aaa.
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Understanding of basic terminology of electronics. ▫ system in which electronics is one of the component .. N.N. Bhargava, D.C. Kulshreshtha, S.C. Gupta. View Basic Electronics And Linear Circuits_N. N. Bhargava, D. C. Kulshreshtha resourceone.info from MECHANICAL PHX at National Institute of Technology. PDF for free at The Biggest ebook library in the world. Get basic electronics and linear circuits nn bhargava PDF file for free on our ebook library. PDF File: basic.
Bhargava — Google Books Paperbackpages. Thanks for telling us about the problem. The text on Basic Electronics and Linear Circuits icrcuits a fundamental approach in discussions on electronics and treats the subject matter in a manner to empower practical implementation of the concepts. Lists with This Book. Tutorial sheets at the end of each unit to help students practice and reinforce the concepts learns. Share your thoughts with other customers. Sponsored Products are advertisements for products sold by merchants on Amazon.
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Basic Electronics and Linear Circuits 3. Connect with Us Facebook Twitter Instagram. To see what your friends thought of this book, please vy up. The strip is then bent into a round shape. Figure 1. A capacitor offers low impedance to ac. Available capacitances range from 5 to 10 pF. Capacitance is a measure of a capacitor's ability to store charge.
Since the two plates of a capacitor can be of many different b Mica capacitors Fig. A capacitor is basically meant to store electrons or electrical energy. During the manufacture of the capacitor. The tapered strip gives a nonlinear variation of resistance with the rotation of the moving contact. Some of the most commonly used fixed capacitors are mica. The strip can be tapered suitably so as to obtain a desired variation in resistance per unit rotation of moving contact.
Ceramic capacitors Ceramic capacitors are made in many shapes and sizes. Then the entire unit is coated with plastic and marked with its capacitance value--either using numerals or a colour code. In the linear type. Ceramic capacitors are very versatile. The mica capacitors have excellent characteristics under stress of temperature variations and high voltage applications.
The 'pots' used as volume control in sound equipment are generally of the non-linear type logarithmic variation. The plates are connected to two electrodes.
A capacitor consists of two conducting plates. It is also used as a bypass capacitor. Their work-. In this role. Its leakage current is very small R1eakage is about MO. A ceramic disc is coated on two sides with a metal. Variable capacitors are mostly air-gang capacitors.
Mica capacitors are usually rated at V. The circuit symbol of a capacitor is shown in Table 1. Resistance wire "-. In a non-linear. Introduction to Electronics 13 Basic Electronics and Linear Circuits 12 conducting materials and the dielectric may be of many different insulating materials.
The colour coding is similar to that used for resistances. To make a potentiometer of this type. These coatings act as the two plates see Fig.
Mica capacitors Mica capacitors are constructed from plates of aluminium foil separated by sheets of mica as shown in Fig. It is measured in farads F. The voltage ratings may range from 1 V to V. These capacitors are commonly used in situations where a large capacitance is required. They can be used for both de and ac circuits.!. Electrolytic capacitors Electrolytic capacitors are extremely varied in their characteristics.. This paper is impregnated with a dielectric material such as wax.
The capacitor consists of two metal foils separated by strips of paper.. Ceramic capacitors have a very low leakage currents R1eakage is about MQ and can be used in both de and ac circuits..
Paper capacitors The basic construction of a paper capacitor is shown in Fig Since paper can be rolled between two metals foils. Various types of electrolytic capacitors are shown in Fig Its leakage resistance is of the order of MQ.!.
This reaction of the magnetic field. This magnetic field reacts so as to oppose any change in the current.
Basic Electronics And Linear Circuits_N. N. Bhargava, D. C. Kulshreshtha And.pdf
The aluminium plate serves as the positive plate and the oxide as the dielectric. To avoid power losses. Filter chokes These are the inductors used in smoothing the pulsating current produced by rectifying ac into de.
The capacitor should be properly connected so that the applied voltage encounters the high resistance. It is primarily designed for use in circuits where only de voltages will be applied across the capacitor. Many power supplies use filter chokes of 5 to 20 H. In some applications. A new type of electrolytic capacitor is the tantalum capacitor. This is done by means of a variable capacitor. This semiconductor blocks the current coming through the oxide film toward the electrode. The aluminium oxide layer is very thin.
The container then serves as the negative terminal for external connections. The oxide is in contact with a paper or gauze saturated with an electrolyte. The greater the common area.
The dielectric for this capacitor is air. The most common variable capacitor is the air-gang capacitor shown in Fig. In most cases. Variable capacitors In some circuits. The inductance is measured in hemys H. It has an excellent capacitance-to-size ratio. A typical filter choke has many turns of wire wound on an iron core. Ordinary electrolytic capacitors cannot be used with alternating currents.
By rotating the shaft at one end. It has high capacitance-to-size ratio. All inductors. The reason for the polarised positive and negative electrodes nature of the capacitor is that the aluminium foil and the aluminium oxide layer form a semiconductor.
Different types of inductors are available for different applications. The symbols of an air-core and an iron-core inductor are shown in Table 1. Both mica and ceramic are used as the dielectric for trimmer capacitors. In such situations we use a variable capacitor called a trimmer sometimes called padder. One setting is sufficient for all normal operations. Another layer of aluminium without the oxide coating is also provided for making electrical contact between one of the terminals and the electrolyte.
The electrolyte forms the second plate negative of the capacitor. Such chokes are called radio-frequency chokes RFCs. Basic Electronics and Linear Circuits 18 2. Audio-frequency chokes AFCs They are used to provide high impedance to audio frequencies say. Chokes having still smaller inductances are used to block the radio frequencies.
If the number of turns in the secondary is less than that in the primary One of these inductors. Active Components Table 1. In a step-up transformer. Table 1. The transformer is then called a step-down transformer. A transformer of suitable turns-ratio is often used in electronic circuits for impedance matching.
Variable inductors are used in tuning circuits for radio frequencies. The other is called secondary. This shaft can be moved within the coil to vary the inductance as shown in Fig. It consists basically of two inductors having the same core Fig. The permeability-tuned variable coil has a ferromagnetic shaft. The secondary voltage is more than the primary. Compared to filter chokes. Transformers A transformer is quite similar in variable coil appearance to an inductor.
A system of units is said to be coherent if the product or quotient of any two unit quantities in the system is the unit of the resultant quantity without the introduction of any numerical factor. Time The second is the duration of 9 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium atom.
The definitions of these base units are as follows: Table The SI units are based on seven base units with a unit symbol assigned to each of them as given in Table 1.
Length Fig. Luminous intensity The candela is the luminous intensity. This system of units possesses features that make it logically superior to any other system and also more convenient. The definitions of various units given in the Act conform to the definitions of the SI units. Mass The kilogram is equal to the mass of the international prototype kilogram stored at Sevres.
In Electric current The ampere is that current which. Double or compound prefixes should be avoided. The SI units cover all fields of physics and engineering. The radian is the plane angle between two such radii of a circle which cuts off. Some symbols. A complete list of such factors is given in Table 1. The guidelines for the application of these prefixes are as follows: These are known as supplementary units. For instance. To simplify calculations.
The rules for binding-in indices are not those of ordinary algebra. Exceptions are kilQ. When a compound unit is formed by dividing one unit by another. It is recognised. In the 1 former notation. How has electronics affected our daily life? Write at least two important applications of electronics in the field of a communications and entertainment. Explain briefly the basic construction of a ceramic capacitor.
Nm for newtons x metres and kWh for killowatt hour. There is a mixture of capital and lower-case letters in the symbols for the prefixes as shown in Table 1.
The symbols for a unit. A space is left between the symbols for compound units. The groups should be separated by a small space. To facilitate the reading of numerals. What is the range of wattage for wire-wound resistors?
Why are paper capacitors not used in filters of rectifier power supplies? Algebraic symbols representing "quantities" are written in italics Write the unit ofresistance? If a resistor is rated at Q and 10 W.. When expressing a quantity by a numerical value and a certain unit. Explain in brief. Justify the statement in about lines. They are printed in full or abbreviated.: Full names of units.
Units may be written out in full or using the agreed symbols. A space is left between a numeral and the symbol except in case of the permitted non-SI units for angular measurements.
Symbols for units do not take a plural form with added 's'. Name three primary uses of capacitors? This type of confusion will not occur if we follow the rule that the denominators of compound units are always expressed in the base units and not in their multiples or submultiples.
What is the range of capacitance values available in ceramic capacitors? In complicated cases. Explain constructional features of a wire-wound resistor. What are the modem trends in electronics? Symbols for other units are not written with capital letter. Before understanding electronic circuits. No full stops or hyphens or other punctuation marks should be used within or at the end of the symbols for units.
A few examples are given below: Correct Incorrect a b State what is meant by radar? Mention some of its important applications In numerals of four digits.
What is meant by electronics? Give some important applications of inductors. When we rotate the tuning control. The term IC. What is a trimmer capacitor? Describe the basic construction of a mica trimmer capacitor.
The colour bands on a fixed carbon resistor are: What is an inductor? What is the unit of inductance? When you adjust the volume control knob of your radio receiver.
Choose the alternative that completes the statement correctly. Write down the seven base units in SI units. A resistor has a colour band sequence: The sequence of the colour band on this resistor should be a yellow. By rotating the volume control in a radio receiver. Electronics is that branch of engineering which deals with the application of a high-current machines b production of electronic components c electronic devices d fission of uranium nuclei From this information.
Below are some incomplete statements. For what purpose can a transformer be used in an eJectronic circuit? Which one of the following is used as a passive component in electronic circuits? Four alternatives are provided for each.. With the help of a computer. When you rotate this control. Such a large value of capacitance is possible if the capacitor is a a mica capacitor b a ceramic capacitor d an electrolytic capacitor c an air-gang capacitor Introduction to Electronics 27 6.
One of the examples of an active device is a an electric bulb b a transformer c a loudspeaker d a silicon controlled rectifier SCR 3. What forms the dielectric of an electrolytic capacitor? Why is the electrolytic capacitor polarised? Name a few active components devices used in electronic circuits.
With the help ofradar. While tuning your radio receiver to a desired station. May it not be identical with it. A source is. The source may supply either de direct current or ac alternating current.
The terminology de as employed here stands for any quantity that is steady.. An ac voltage can be converted into a unidirectional voltage by using a a power amplifier circuit b an oscillator circuit c a multivibrator circuit d a rectifier circuit Answers. The secondary cell is rechargeable. But the cells used in a torch are of primary type. These ions carry the charge inside the cell from one electrode to the other.
It has a rotating shaft. When dissolved in a solution. Solar cells are in the developmental stage. A battery consists of a series or parallel combination of two or more similar cells. Generally speaking. Each has two electrodes one positive and the other negative which are immersed in an electrolyte.
The adaptor used with a laptop is also of this type. When its shaft is rotated. A de laboratory supply ofthis type is shown in Fig. Some de sources are battery.
The battery used in a car is of secondary type. Cells can be divided into primary and secondary types.. The term battery is derived from the expression "battery of cells".
A cell is the fundamental source of electrical energy.
When this shaft is rotated at the specified speed by some external agency such as a steam turbine or water turbine. Figure 2. These type of alternators are used in most electric power stations. Electronics has hardly anything to do with such alternators. Unless stated otherwise. A battery and some cells Fig. This process will be discussed in detail in Unit 4.
It contains a rectifier which converts time-varying voltage. Electrolytes are chemical compounds. The terminal voltage VT is -. Since the net voltage that sends current into the circuit is 1. The total resistance in the circuit is now 0. Some signal generators are capable of giving other type of waveforms. The frequency of the ac signal supplied by this instrument can be varied. In the equivalent circuit of Fig.
Let Vs be its open-circuit voltage i. Under this condition. When a voltage source supplies power to a load. Such a reduction in the terminal voltage of the cell may be explained as follows.
The resistance of the electrolyte between the electrodes. A cell used in a torch has a voltage of 1. It is due to this internal impedance that the source does not behave ideally. It means that the terminals AB of the source are open-circuited. The internal resistance or impedance in case of ac source of a source may be due to one or more of the following reasons: Let it be connected to a load impedance ZL whose value can be varied.
The resistance of the armature winding in case of an alternator or a de generator. The output impedance of the active device like a transistor in case of an oscillator or signal generator and rectification-type de supply.
Basic Electronics and Linear Circuits
When we say "cell of 1. This voltage is used as a signal to test the working of different electronic circuits such as an amplifier. I 1Vs. It it could do so.. A practical voltage source can be considered to consist of an ideal voltage source in series with an impedance.
In Eq Let us now connect a finite load impedance ZL. Load impedance. Load current.. This is not possible. The symbolic representation of de and ac ideal voltage source are given in Fig.
When we reduce the value of load impedance. As we do this. This impedance is called the internal impedance of the source. The symbolic representation of practical voltage sources are shown in Fig. Even if the load impedance changes. As a result. Such a source can then be said to. The voltage drop across Zs also goes on increasing. There is no source which can maintain its terminal voltage constant when its terminals are short-circuited. V-1 characteristics of an ideal voltage source Fig.
In other words. When the load resistance becomes 10 Q These are the terminals available for making external connections. A Q. In the de source. OV xRu With respect to the maximum value. In the first case. In the ac source in Fig. When the load resistance varies between its extreme limits-from 1 Q to 10 Q-the terminal voltage varies from 1 V to 1.
In the next half-cycle of ac. When the load resistance RL is 1 Q. We can find the variation in the terminal voltage of the source. Let us now find the variation in the terminal voltage of the source. This is certainly a large variation. In some books. In the second case.
Let us consider an example. It is connected to a load resistance RL as shown in Fig. It is the value of the internal impedance relative to the load impedance that is important. The marking of positive and negative on an ac source does not mean the same thing as the markings on a de source.
Let us consider another example. When the load impedance is 50 ill. We can again find the terminal voltage as The question naturally arises: What should be the characteristics of a source so that it may be considered a good enough constant voltage source?
An ideal voltage source. B a Fig. Here in ac.
A de source has an open-circuit voltage of 2 V. The load impedance ZL can vary from 50 ill to kQ-again a variation having the same ratio of 1: In practice. The symbolic representation of such a practical current source is shown in Fig.
A practical current source is represented by the symbol shown in Fig. It means there should be some path inside the source itself through which the current Is can flow. The inside path has an impedance Zs. The source impedance Zs is put in parallel with the ideal current source ls. That is why. The reason why an actual source does not work as an ideal current source is that its internal impedance is not infinite.
The V-1 characteristic of a practical voltage source then looks like the one shown in Fig. It will become clearer in later chapters. The introduction of semiconductor devices such as the transistor is responsible. It is sometimes preferred to take voltage on the x-axis and current on the y-axis.
Of course. When some finite load impedance is connected. If the source could maintain a current Is through an infinitely large load impedance. When the load current increases. The characteristic is then modified to that shown in Fig..
The remaining current goes through the path Fig. Do not be alarmed if the concept of a current source is strange and somewhat confusing at this point.
Let us find the conditions under which a source can work as a good practical current source. As stated above. It is now an infinite value. It means even if ZL is made infinity.
Let us connect a variable load impedance ZL to a constant current source as shown in Fig. When the load impedance ZL is made infinite i. It means that the source does not have to supply infinite power. The arrow inside the circle indicates the direction in which current will flow in the circuit when a load is connected to the source. A symbolic representation of such an ideal current source is shown in Fig.
It would then have consumed infinite power from the source. The current Is now divides itself between two branches--one made of the source impedance Zs inside the source itself.
In Fig. Let us find out the open-circuit voltage in the current-source representation of Fig. For a given increase in load impedance ZL. From the circuit point of view.. In other words.. There is no voltage drop across the internal impedance Zs1. In fact.. If the value of the load impedance is very large compared to the internal impedance of the source. The terminal voltage is then the voltage drop across this imped.
But the current obtained by shorting the terminals A and B of Fig. When the terminals A and B are open-circuited. On the other hand. The V-I characteristic of a practical current source is shown in Fig. The source then behaves as a good current source.
That is 2. In fact. It merely depends upon Again. This means that current source in Fig. These are the two representations of the same source. SX L2 - By making use ofEq. The source impedance of 1 Q is connected in parallel with this current source. IQ 'eB Fig. Since the current divides itself into two branches in inverse proportion of the impedances. To test this. The equivalent current source obtained is shown in Fig. We may convert a given voltage source into its equivalent current source by using Eq.
Ifwe short circuit the terminal A and B of the voltage source. The current in the 40 kQ impedance can be determined as follows: We can connect the net load impedance ZL of 8 kQ. Here we convert the given current source into its equivalent voltage source. The current [z divides into two parallel branches. The source impedance Zs is put in series with the ideal voltage source. The loop current can be calculated by applying Kirchhoff's voltage law. A r-'..
Example This would be the parallel combination of the two impedances. The circuit in Fig. The open-circuit voltage of the source is given as 3 r-'.. A 8kQ 3. A net impedance of 8 kQ is shown to be connected across the source terminals A and B. ZL A current source connected to a load Solution: Let us first determine the net load impedance that is connected across the source terminals A and B..
The open-circuit voltage across terminals A and B. When the load current varies. Its symbol is shown in Fig. It the load impedance RL varies. We need another voltage source for its operation. We can now apply the basics of circuit theory to determine the characteristic behaviour of the electronic circuit. B Fig. This is an example of simple voltage regulator circuit. Loosely speaking. Once it is connected in an electrical circuit.
Another important device is the transistor. The transistor is extensively used as an amplifying device. The only difference is that the characteristic curve of the zener diode is inverted. It is shown inverted to emphasise that the zener diode is operated with reverse bias the term reverse bias is explained in detail in Unit 4. These terminals are called emitter. When connected in the amplifier circuit. This current gets divided into two parallel branches of the load impedance ZL see Fig.
If the zener diode were not there. Strictly speaking. It ensures safe operation of the zener diode. The terminal voltage VT remains constant at Vz whatever be the current flowing through the zener diode. But now. The current through the 40 kQ impedance is varies. For the time being. This means that the current through the zener diode flows in a direction opposite to that of the arrow in its symbol.
In this equivalent circuit. The resistance R 2 is put in the circuit so as to limit the current through the zener diode. It is a three-terminal device. Name two sources of electrical power. How can you convert one representation to the other? Transistor Fig.
BASIC ELECTRONICS AND LINEAR CIRCUITS BY N.N.BHARGAVA PDF
Justify your answer ill about three lilies. The equivalent representation of the transistor as shown in Fig.. A practical source can be represented either as a voltage source or as a current source..
Draw the symbolic representation of a practical current source. Explaift the reason for putting an impedance ill this symbolic representation..
BASIC ELECTRONICS AND LINEAR CIRCUITS BY NN BHARGAVA EBOOK DOWNLOAD
Explaift the condition under which a practical voltage source is considered to be good voltage source. This resistance has high value typically. State an application of an electronic device whose characteristics are similar to that of an ideal voltage source.
The ac behaviour of the transistor can be represented by the circuit shown in Fig. Explain ill one or two lines its characteristics. Explaift the necessity of includiftg an impedance in the representation. The value of the ac current source ic depends upon the input ac current ie. This resistance represents the source resistance when we look upon a transistor as a current source.
Draw the symbol of an ideal current source.. Output I I: Draw the symbol of an ideal de voltage source.. Below are some iftcomplete statements. It is meant for the de operation of the transistor. Between its output terminals collector and base. Four alternatives are provided for each. Are they voltage sources or current sources? Such characteristics are very similar to the characteristics of a current source as shown in Fig. Name an electronic device which has characteristics similar to that of an ideal current source.
The current i can be calculated from the input circuit. The value of the current source in ac equivalent of the transistor is lOOi. Draw the symbolic representation of a practical ac voltage source.
Name at least one electronic device whose characteristics are very close to that of an ideal voltage source. The resistance R 0 represents static de output resistance. I 2kQ Vo 5. If the load impedance is doubled. In a practical voltage source. ICLiF 7. A device whose characteristics are very close to that of an ideal voltage source is a a silicon signal diode b transistor in common-base mode c field-effect transistor d zener diode 5.
The current flowing through the zener diode in Fig. An ideal current source has low internal resistance. An ideal current source has infinite internal resistance. An ideal current source is one whose internal resistance is a very high b very low c zero d infinite 3.
A constant current source supplies a current of mA to a load of 1 kQ. A resistance is connected to a practical source. An ideal voltage source is one which has a very high internal resistance b very low internal resistance c zero internal resistance d infinite internal resistance 2. A practical current source has low internal resistance. When the load is changed to Q. For finding the current through this resistance. An ideal voltage source has zero internal resistance. Figure 0. The constant voltage available across the zener diode is 5 V.
An ideal voltage source of 12 V provides a current of mA to a load. The current flowing through the 1-kQ load is Current and Voltage Sources 8.
The output side of a transistor connected in common-base mode should be treated as a constant voltage source. Answers 'f Cc Fig. Below are some statements.
Solving an electrical circuit will give the same results whether the source is treated as voltage source or as current source. A device whose characteristics are very. A zener diode has characteristics similar to that of an ideal current source.
A practical voltage source has very high internal resistance. An ideal voltage source has low internal resistance. Indicate against each. The voltage gain of an amplifier is defined as the ratio of its output voltage to its input voltage..
Calculate the voltage v 0 in Fig. Figure T. Identify the source impedance Zs. Convert it into an equivalent voltage source. A Calculate the voltage available between the points A and B in the two situations represented in Fig. Figure T.. Tutorial Sheet I [Ans. State which situation represents a better voltage source condition. Convert it into an equivalent current source.
Assume that the zener diodes have ideal voltage-source characteristics. An electronic amplifier is used to amplify electrical signals. Calculate the current through the kQ resistor shown in Fig.
I rt 15 kQ "Electronic aids. If one looks inside any electronic equipment. Reality is no longer going to be the stuff out there. This means the diode is conducting and the current is flowing in the circuit. To understand the operation of these devices and many more that are likely to come in future. The conductivity of the semiconductor can also be controlled by controlling the amount of impurity added to it. Another important component is the transistor. In this respect. These coverings provide protection against short circuits and also against electrical-shock hazards.
The diode makes it possible to convert ac into de. It is for this reason that these materials are classified as semiconductors. Insulating materials are bad conductors of electricity. Conducting materials are good conductors of electricity. According to a simplified picture.. The unidirectional conducting property of a diode finds great applications in electronics.
It has a very important property of conducting in one direction only. When we raise the temperature of a semiconductor.. Table 3. When the diode is connected in this manner. These are neither good conductors nor good insulators. It means no current is flowing in the circuit. It is used for amplifying weak electrical signals.
In modem electronic systems. Quite often. We know that the most fundamental unit of matter which is capable of independent existence is the atom. The electrical wire used in Resistivity Qm. Classification Conductors Semiconductors Insulators 16 When we increase the temperature of a metal conductor such as copper. There is another group of materials. Let us take a simple example of a semiconductor diode.
Examples of insulators are porcelain. Figure 3. The core provides an easy path for the flow of electric current This core is covered with some insulating material such as rubber. Examples of good conductors are copper. We already know something about resistors.Related titles. To get the free app, enter mobile phone number. AmazonGlobal Ship Orders Internationally. On the other hand. With such wireless communication radio broadcasting , people in any part of the world can know what is happening in othe.
These ions carry the charge inside the cell from one electrode to the other. What is an inductor? Convert it into an equivalent voltage source.
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