Previous year question paper for E1 (Diploma Electrical Engineering 3rd)

1. Introduction (5 hrs)

1.1 Brief history of development of electronics (vacuum tube to solid

state)

1.2 Active and passive components

1.3 Concept of current and voltage sources, constant voltage and

current sources, their graphical representation. Conversion of

voltage source into current source and vice-versa

1.4 Difference between actual voltage source and constant voltage

source

2. Semi-conductor Theory (10 hrs)

2.1 Atomic structure, crystalline structure

2.2 Energy band theory of crystals, energy band structure of insulator,

semiconductor and conductor, generation and recombination of

electron hole pairs. Energy band structure of Silicon and

Germanium

2.3 Silicon versus Germanium for mobility and conductivity

2.4 Concept of Doping, intrinsic and extrinsic semiconductors

2.5 Effect of temperature on intrinsic and extrinsic semiconductors

3. Semiconductor Diodes (10 hrs)

3.1 PN Junction, mechanism of current flow in PN junction, drift and

diffusion currents, depletion layer, potential barrier, effect of forward

and reverse biasing in a PN junction. Concept of junction

capacitance in forward and reverse biased conditions. Breakdown

mechanism

3.2 Ideal diode, Semiconductor diode characteristics, static and

dynamic resistance

3.3 Use of diode as half wave and full wave rectifiers (centre tapped

and bridge type), relation between DC output and AC input voltage,

rectifier efficiency

3.4 Concept of ripples, filter circuits – shunt capacitor, series inductor,

and pie (π) filters and their applications

3.5 Diode ratings/specifications 

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3.6 Various types of diodes such as zener diode, varactor diode,

schottky diode, light emitting diode, tunnel diode, photo diode; their

working characteristics and applications

3.7 Zener diode and its characteristics

3.8 Use of zener diode for voltage stabilization

4. Bi-polar Transistors (7 hrs)

4.1 Concept of junction transistor, PNP and NPN transistors, their

symbols and mechanism of current flow

4.2 Transistor configurations: common base (CB), common emitter (CE)

and common collector (CC), current relation and their input/output

characteristics; comparison of the three configurations

5. Transistor Biasing and Stabilization (8 hrs)

5.1 Transistor biasing, its need, operating point, effect of temperature

on the operating point of a transistor and need of stabilization of

operating point.

5.2 Different biasing circuits, limitations, simple problems to calculate

operating point in different biasing circuits. Use of Thevenin’s

theorem to determine operating point

5.3 Concept of h-parameters of a transistor

5.4 Use of data book to know the parameters of a given transistor

6. Single-Stage Transistor Amplifiers (10 hrs)

6.1 Single stage transistor amplifier circuit in CE configuration, function

of each component

6.2 Working of single stage transistor amplifier, physical and graphical

explanation, phase reversal

6.3 Concept of DC and AC load line

6.4 Voltage gain of single stage transistor amplifier using characteristics

of the device

6.5 Concept of input and output impedance

6.6 AC equivalent circuit of single stage transistor amplifiers

6.7 Calculation of voltage gain using AC equivalent circuit

6.8 Frequency response of a single stage transistor amplifier

7. Multi-Stage Transistor Amplifiers (7 hrs)

7.1 Need of multi-stage transistor amplifiers – different types of

couplings, their purpose and applications.

7.2 Knowledge of various terms such as voltage gain, current gain,

power gain, frequency response, decibel gain and band width

7.3 RC coupled two-stage amplifiers, circuit details, working, frequency

response, applications

7.4 Loading effect in multistage amplifiers

7.5 Elementary idea about direct coupled amplifier, its limitations and

applications

7.6 Transformer coupled amplifiers, its frequency response. Effect of

co-efficient of coupling on frequency response. Applications of

transformer coupled amplifiers 

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8. Field Effect Transistor (FET) (07 hrs)

8.1 Construction, operation, characteristics and applications of a N

channel JFET and P channel JFET

8.2 JFET as an amplifier

8.3 Types, construction, operation, characteristics and applications of a

MOSFET

8.4 Comparison between BJT, JFET and MOSFET