## Units and Topics

## Syllabus

Development of vacuum tube devices, semiconductor devices, integrated circuits, microprocessors & microcontrollers.

- entertainment, communication, defense, industrial & medical.
- Impact of electronics on quality of life

- Charge-positive and negative charges, properties of charges, S.I Unit of charge, Charge of an Electron, Number of electrons in one Coulomb of charge, Electric Current-definition (charge/sec), its unit and direction of current- conventional current and the electronic current. Potential difference and its unit related to electric circuit, Direct current (DC) and Alternating Current (AC)- representation and examples of DC & AC sources.
- Ohm’s law-statement & limitations, application to circuits. Resistance and its unit, Electric Power-definition, unit of power, electric energy-definition and Power dissipation in resistors -Power formulae and Energy formula. (P = VI, R V P 2 P = I 2R & kWh).
- Combinations of resistors-series, parallel-derivations of the expressions, series – parallel - circuits and problems. open and short circuit – Problems

- Introduction to secondary DC sources like dry cells and other type of batteries, internal resistance of sources, Voltage sources: Definitions, Conversion of voltage source to current source and vice versa.
- Kirchhoff’s current law and Kirchhoff’s voltage law, current and voltage division, problems up to two loops on Kirchhoff’s laws.
- Network theorems: Thevenin’s theorem, statements, respective equivalent circuits for dc networks. Super position theorem, statement, analysis with two voltage sources, Maximum power transfer theorem- statement (no derivation) all theorems with respect to DC circuit. Problems on each theorem.

Expression for the instantaneous voltage v =Vmsin(t) (no derivation), definitions of frequency, time period, peak value, r.m.s value, effective value and average value with reference to sinusoidal waveform. Different types of non sinusoidal waveforms square, triangular and saw tooth- mention only.

Voltmeter (AC/DC), ammeter (AC/DC) & Ohm meter – photograph of each one, symbol & uses of each, with diagrams study front panel details of a typical multimeter and a dual channel oscilloscope, use of oscilloscope for measurement of voltage (AC/DC), time period & frequency, precautions while using electronic instruments.

Electrocardiography (ECG), sphygmomanometer (blood pressure instrument), glucometer, ultrasound scan, pulse oximeter, clinical digital thermometer – use of each one.

Comparison of passive and active components- Passive and active components, their examples

resistance of conductor & its unit, specification of resistors, temperature coefficient of resistor, specific resistance, types of resistor – fixed and variable, Fixed resistors - carbon composition, metal film & SMD resistor, constructional aspects in brief and applications of resistors.

Construction, applications.

Potentiometer – carbon composition type - construction and uses, Preset. Importance of power rating in resistors Color coding of resistors (4 bands & 5 bands), tolerance, and problems

- Definition of Capacitance and its unit - Principle of capacitor, factors affecting the capacitance of capacitor, parallel plate capacitor (mention C = oA/d and C = orA/d-no derivation), energy stored in a capacitor E = ½CV2 (no derivation), dielectric and examples, role of dielectric in capacitor.
- Types of Capacitors – fixed and variable.
- Fixed capacitors: Ceramic, Polystyrene, SMD capacitor and Electrolytic capacitor - construction and applications.
- variable capacitors like ganged capacitor and trimmer - their applications Importance of voltage rating in capacitors.
- Capacitive networks - derivation of expressions for effective capacitance of capacitors connected in series or in parallel trouble shooting in capacitors - open short, leakage.

- Review of laws of electromagnetic Induction Definitions of self, mutual inductances and unit of Inductance. Inductor - factors determining the inductance of inductor μN A L 2 Energy stored in an inductor i.e., E = ½ LI2 (no derivation), Fixed Inductors: Air core, iron core, ferrite core - construction and applications. Expressions for series and parallel combination of inductors neglecting the mutual inductance (no derivations), choke and relays.
- Transformers: Principle (mutual induction), Turns ratio, voltage ratio and current ratio - relation between them, step up and step down transformers, Centre tapping in transformers, problems, applications of transformers, Efficiency in transformers, AF & IF transformers, pulse transformer.

Definition of transducer, pressure transducers - microphone and loud speaker - construction, working and applications, Temperature transducers [Thermistor-Negative Temperature Coefficient (NTC) and Positive Temperature Coefficient (PTC) - only mention], LM 35 temperature sensor, LDR, Applications of temperature transducer

Transient phenomenon, transient period, Charging & discharging of a capacitor in RC circuit - expressions (mention only-no derivations), definition of Time constant, graphical representations for charging & discharging of a capacitor. Growth and decay of current in RL circuit - expressions (no derivations), definition for Time constant, graphical representations for growth and decay of current. Problems on RC & RL circuits.

Concept of phase and phase difference. AC applied to resistive circuit: Phasor representation of voltage and current waveforms. AC applied to capacitive circuit: Circuit diagram, Expression for instantaneous current and voltage for a sinusoidal input voltage, Phasor representation of voltage and current, definition of phase, phase difference - Lead and lag concepts. AC applied to inductive circuit: Circuit diagram, Expression for instantaneous current and voltage for a sinusoidal input voltage, Phasor representation of voltage and current, definition of phase, phase difference - Lead and lag concepts. Resistance, reactance and impedance. Capacitive reactance and inductive reactance-definitions and expressions. Power in AC circuit: Power factor, active and reactive power. Series RLC circuits: Impedance, impedance equation (mention only), variation of impedance with respect to frequency. Series Resonance - Condition for resonance, Resonant frequency, Half power frequencies, BW, Quality factor in terms of fr & BW. Frequency & phase response of RC circuits: Brief note on filters and its application. Low pass and high pass filters - frequency response and phase response graph and Cutoff frequency, problems

Band theory of solids - valence band, conduction band and the forbidden energy gap, Classification of solids as conductors, semiconductors and insulators on the basis of their conductivity and on the basis of energy band diagrams, examples for each. Types of semiconductors - Intrinsic and Extrinsic. Intrinsic semiconductors: Definition, lattice structure (two dimensional), concept of holes and electrons (their generation and flow in the bands), effect of temperature, thermal generation and recombination of electrons and holes. Extrinsic semiconductors: Definition, doping, doping elements - trivalent and pentavalent, meaning of donor and acceptor impurities. Types of Extrinsic Semiconductors: n type and p type, their formation, in each case study of lattice structure (two dimensional).

Formation of pn junction, diffusion of charge carriers, depletion region - formation of depletion region, barrier width and barrier potential, semiconductor diode. Forward biased pn junction: Diagram, Effect on width of the depletion region, resistance and current flow. Reverse biased pn junction: Diagram, Effect on width of the depletion region, resistance and concept of leakage current (in germanium and silicon), junction capacitance (during reverse bias) and its variation with applied reverse bias voltage, brief note on breakdown mechanisms.

Circuit symbol, Diode equation Numerical problems need not be discussed. Ideal and practical diodes, Equivalent circuit of a practical diode (barrier potential in series with Rf). V-I static characteristics - Circuits to study the forward bias and reverse bias characteristics, characteristic curves, knee voltage, forward bias resistance from characteristic curve. Study of various terms related to diode like PIV and power rating (qualitative), diode approximations, Comparison of Germanium and Silicon diodes. Wave shaping circuits – clippers – series positive clippers, series negative clippers, clampers - positive clampers, negative clampers.Rectification – Need for rectification, Principles, Half wave rectifier, Full wave rectifier (centre tapped and bridge type): Circuit, working of rectifiers considering transformers at the input, input and output wave forms for the rectifiers. Expression for Load regulation - mention only. Expressions (no derivations) for average output voltage Vav, average output current Iav, Vrms and Irms. Efficiency ‘’ (expression - no derivation), Ripple and Ripple factor (expressionno derivation) for each case, comparison of rectifiers. Concept of negative voltage rectifiers. Problems.

Need for filters, series inductor filter, shunt capacitor filter and Inductive input L type filter, - circuit diagram, working and waveforms for each type, bleeder resistance.

Zener diode: schematic symbol, Zener and avalanche breakdown, V-I characteristics of Zener diode, its application in voltage regulation-study of line and load regulation, Calculation of minimum load resistance required for regulation - problems with constant input & variable input voltage. Design of practical regulated power supplies – Design of a rectifier for a given DC voltage, Fixed positive regulated power supply using 7812, Fixed negative regulated power supply using 7912 & Adjustable regulated power supply using LM317. Specifications of DC regulated power supply. Light Emitting Diode (LED) - symbol, construction - type of materials used, working in brief and applications. Varactor diode, IR emitter diode, photo diode, tunnel diode & Schottkey diode - symbol, and applications. Seven segment display: LED display - pin configuration showing the different segments-a, b, c, d, e, f, g and dp. Common Anode and Common Cathode display. Display of digits 0 to 9, use of current limiting resistors for each segment, applications. LCD (Liquid Crystal Display), Comparison of L.E.D displays with L.C.D displays.

Transistor working-npn (in active mode), Symbols, currents IB, IC and IE, Three basic configurations of transistor – CE, CB and CC. DC current gains and β and the relationship between them. Input and output characteristics of a transistor in CE configuration. Meaning of cutoff, saturation, and active regions. Photo transistor, Opto-coupler & IR receiver transistor – working in brief, symbol & applications.

Introduction, importance of Digital Electronics, representation of digital and Binary signals, Positive and Negative logic. Number systems – Need for the study of various number systems, Decimal number system, and Binary number system – advantage, bit, nibble, byte, memory representation using Bytes, hexadecimal number systems, conversion from one system to another. Binary addition, subtraction, multiplication and division, 1’s complement, 2’s complement, 1’s complement and 2’s complement method for subtraction of binary numbers (subtraction of a binary number of smaller value from a number of larger value), sign magnitude binary number. Boolean algebra and Logic gates: Boolean Algebra: Introduction to Boolean Algebra, Basic Boolean operators (OR, AND and NOT operators), Basic Laws and theorems of Boolean Algebra, De Morgan's theorems and their verification, Boolean identities, Simplification of Boolean expressions, Basic Logic gates: OR gate and AND gate: Logic symbol, truth table and realization using diodes, NOT gate - using transistor, logic symbol and truth table. (Positive logic is to be dealt in all cases). Construction of logic circuits for logic expressions. DTL - NAND, DTL - NOR gates – working and truth table. Pulse (clock) generator using 555 - Astable multivibrator - frequency & duty cycle, monostable pulse generator – pulse width.

[Note: photographs, important specifications, part numbers (wherever possible) of each component to be mentioned] Components part numbers, data sheet, package Resistors – CFR, MFR, SMD resistor, wire wound resistor, fusible Resistor. Potentiometer & trimmer resistors Capacitors – Mica, ceramic, polystyrene, electrolytic, SMD capacitor, trimmer capacitor Inductors – air core, iron core, ferrite core Electromagnetic relay Transformers – Iron core, ferrite core Diodes – rectifying diodes, diode bridge module, switching diodes, Zener diode, LEDs, seven segment display, LCD display. Transistors – npn & pnp transistors Sensors: speaker, microphone, temperature sensor, thermistor, LDR, IR emitter diode, IR receiver transistor Regulators- Fixed regulator: 78XX series, 79XX series, PCB Design & development.