BASIC ELECTRONICS

BASIC ELECTRONICS By MANISH SHARMA for more info : http://goodwisher.com/

ECE-101F BASIC ELECTRONICS • L T P Sessional : 50 Marks • 3 0 0 Exam : 100 Marks • Total : 150 Marks • Duration of Exam : 3 Hrs • Note: • Examiner will set 9 questions in total, with two questions from each section and one question covering all sections which will be Q.1. This Q.1 is compulsory and of short answer type. Each question carries equal mark (20 marks). Students have to attempt 5 questions in total. • Section A • Semiconductor Physics: Basic concepts, Intrinsic and extrinsic semiconductors, diffusion and drift currents, p-n junction under open-circuit, reverse bias and forward-bias conditions, p-n junction in the breakdown region, Ideal diode, terminal characteristics of junction diode. • Amplifiers: Introduction of different types of amplifiers and their characteristics, Principle of amplification, Frequency response of RC coupled amplifiers, amplifier bandwidth and Concept of Cascaded Amplifiers, Feedback amplifiers, Effect of positive and negative feedback on amplifier gain and bandwidth. for more info : http://goodwisher.com/

Section B Oscillators: Criteria for oscillations, Qualitative analysis of LC, RC and Crystal Oscillators, Study of Wein Bridge Oscillators Operational Amplifiers: Op-amps, its characteristics and its applications. Power Suppliers: Introduction and Working of Switched Mode Power Supply (SMPS), Voltage Regulator, Introduction to Inverters and UPS. for more info : http://goodwisher.com/

Section C Digital Electronics: Binary, Octal and Hexadecimal number systems and conversions, Boolean Algebra, Truth tables of logic gates (AND, OR, NOT), NAND, NOR as universal gates, Difference between combinational circuits and sequential circuits, Introduction to flip-flops (S-R & J-K). Electronics Instruments: Role, importance and applications of general-purpose test instruments viz Multimeter Digital & Analog, Cathode Ray Oscilloscope (CRO), Function/Signal Generator. for more info : http://goodwisher.com/

Section D Displays : Seven segment display, Fourteen segment display, Dot matrix display LED Display : Introduction, Construction, Advantage of LEDs in electronics display LCD Display : Introduction; Types of LCD display:- Dynamic scattering and field effect type; Types of liquid crystal cells :- Transmitting type and reflective type; Advantage & disadvantage of LCD display common applications. for more info : http://goodwisher.com/

Books Recommended 1. Sedra A S and Smith K C, “Microelectronic Circuits” 4th Ed., New York, Oxford University Press, New York (1997). 2. Tocci R J and Widmer N S, “Digital Systems – Principles and Applications”, 8th Ed., Pearson Education India, New Delhi (2001). 3. Cooper and Helfrick, “Modern Electronic Instrumentation and Measuring Techniques”, 4th print Prentice Hall of India, New Delhi (1996). 4. Boylestad and Nashelsky, “Electronic Devices and Circuit Theory”, 8th Ed, Pearson Education India, New Delhi (2002). 5. Millman and Grabel, “Microelectronics”, 2nd Ed. Tata McGraw-Hill (1999). 6. Basic Electronics by J.B. Gupta for more info : http://goodwisher.com/

ECE-103F Basic of Electronics Lab 1. To get familiar with the working knowledge of the following instruments: a) Cathode ray oscilloscope (CRO) b) Multimeter (Analog and Digital) c) Function generator d) Power supply 2. a) To measure phase difference between two waveforms using CRO b) To measure an unknown frequency from Lissajous figures using CRO 3. a) Plot the forward and reverse V-I characteristics of P-N junction diode b) Calculation of cut-involtage c) Study of Zener diode in breakdown region 4. To plot and study the input and output characteristics of BJT in common-emitter configuration 5. To find frequency response of a given amplifier and calculate its bandwidth for more info : http://goodwisher.com/

ECE-103F Basic of Electronics Lab 6. To get familiar with pin-configuration of typical op-amp(741) and its use as: a) Inverting amplifier b) Non-inverting amplifiler c) Summing amplifier d) Difference amplifier 7. Use of op-amp as a) Integrator b) Differentiator 8. To assemble Wein Bridge oscillator circuit and calculation of oscillation-frequency and its verification from the observed output 9. To assemble and test 5V/9 V DC regulated power supply and find its line-regulation and loand-regulation 10. Verification of truth tables of logic gates (OR,AND, NOT, NAND, NOR) 11. Verification of truth tables of flip-flops (S-R, J-K) 12. To get familiar with the working and use of seven-segment display. for more info : http://goodwisher.com/

What is Electronics It is derived from electron mechanism which means study of behavior of electron under different condition According to radio engineer (IRE ) a standard definition is “that field of science and engg. Which deals with electron device and their utilization “ for more info : http://goodwisher.com/

Electronics It’s a newcomer in filed of engg. as compared to other branches for more info : http://goodwisher.com/

Applications of Electronics Communications :-Telegraphy , Telephony, Wireless comm., radio & TV Broadcasting Defence App :- Radar (Radio detection & Ranging ) Industrial App:- electronics devics . Automatic control instruments. Medical Instruments :- likes Xray Machines , ECG machines . for more info : http://goodwisher.com/

Applications of Electronics Instrumentation :-measuring instruments like CRO Multimeter Function Generator for more info : http://goodwisher.com/

Introduction What is a Semiconductor? Many materials, such as most metals, allow electrical current to flow through them These are known as conductors Materials that do not allow electrical current to flow through them are called insulators Pure silicon, the base material of most transistors, is considered a semiconductor because its conductivity can be modulated by the introduction of impurities Effect of temp on semiconductor is negative temp cofficient ie with increase in temp resistivity decreases . Conductors obeys ohms law for more info : http://goodwisher.com/

SEMICONDUCTORS Advantages such as:- Compact size Low cost Light weight Rugged construction Long life for more info : http://goodwisher.com/

Structure of an Atom Rutherford model of an atom According to this model : Centre of atom consists of nucleus Proton + neutrons are present in nucleus Electrons revolves around nucleus Rutherford model is comparable to solar system As atom is neutral so no of electron = no of protons for more info : http://goodwisher.com/

Structure of an Atom Its centrifugal force which don’t allows electron to be attracted towards nucleus Charge on electron is 1.6* 10-19 C Mass of electron 9.1*10-31 Mass of proton & neutron 1800 times the mass of electron Atomic no = Proton no. No of proton + No of neutron in nucleus = mass no Eg :-aluminium has 79 proton & 118 neutron So atomic no = 79 & mass no =79+118 for more info : http://goodwisher.com/

Electron orbit & energy level Electron occupy certain rings or shells at fixed distance from nucleus Shell are K L M N O P Q No of electron in shells 2n2 Electrons in outer most orbit are valence electrons Electron volt is unit to measure energy in electron for more info : http://goodwisher.com/

Energy band structures for more info : http://goodwisher.com/

Typical Resistivity Values Conductor Semiconductor Insulator 106 -cm 50 -cm (germanium) 1012 -cm (copper) 50 103 -cm (silicon) (mica) for more info : http://goodwisher.com/

Drift & Diffusion Current Drift current occurs when due to an external applied electric field there exit a steady state drift velocity of electrons & current flowing due to this effect is called drift current v= ụ E ụ = Mobility is defined as avg particle drift velocity per unit electron for more info : http://goodwisher.com/

Diffusion Current Diffusion occur due to concentration gradient It occurs when charge carriers diffuse from point of concentration ,to spread uniformly throughout the volume of a piece of material for more info : http://goodwisher.com/

Atomic bond What happen to electrons in outer most shell when atoms combines or bonds themselves for more info : http://goodwisher.com/

Primary Bond They are the strongest bond for more info : http://goodwisher.com/

Secondary Bond They are weaker than primary bond Attra ction forces exist between atoms for more info : http://goodwisher.com/

Metallic Bond When atom gives up their loosely held valance electron Such a bond exist between loosly held valance electron In a more quantum mechanical view, the conduction electrons divide their density equally over all atoms that function as neutral Fig shows +ve metal ions surrounded by valance electrons for more info : http://goodwisher.com/

Covalent bond Characterized by the sharing of pairs of electrons between atoms for more info : http://goodwisher.com/

Ionic bonding Atoms of one element transfer electrons to other so that both have stable configuration Bond formed by the attraction between two oppositely charged ions. for more info : http://goodwisher.com/

Comparison Bond length is spacing between 2 atoms for more info : http://goodwisher.com/

for more info : http://goodwisher.com/

Fermi level in intrinsic semiconductor • Its simply the ref energy level . • Energy level at which probability of finding the electron n energy units above it in conduction band is equal to probability of finding the holes of n energy unit below valence band . for more info : http://goodwisher.com/

P N Junction • When p type & n type are combined by some technique (ie. Ion implantation or diffusion ) • P type has majority carriers as holes & acceptor ions • N type has majority carriers as electrons & donor ions • There exist a concentration gradient of in P & N for more info : http://goodwisher.com/

P N Junction for more info : http://goodwisher.com/

P N Junction • Diffusion current is due to concentration gradient • Diffusion of holes is from P to N Side • Diffusion of electron is from N to P Side • Holes & electron recombine & uncover bound charges • So a layer of +ve fixed charge is formand on the n side of junction • Layer of -ve fixed charge is formand on the p side of junction for more info : http://goodwisher.com/

P N Junction • A potential barrier is formed across the junction • An electric field is formed because of uncovering of bond charges • Due to this electric field minority charge carries (thermally generated )starts flowing • This gives rise to drift current for more info : http://goodwisher.com/

BASIC ELECTRONICS