Module 4: Electronic Fundamentals

4.1Semiconductors

4.1.1Diodes

(a) Basic:

• Diode symbols
• Diode characteristics and properties
• Diodes in series and parallel
• Main characteristics and use of: silicon controlled rectifiers (thyristors), light emitting diodes, photo conductive diodes, varistors, rectifier diodes
• Functional testing of diodes

(b) Detailed:

• Materials, electron configuration, electrical properties
• P and N type materials: effects of impurities on conduction, majority and minority carriers
• PN junction in a semiconductor, development of a potential across a PN junction in unbiased, forward biased and reverse biased conditions
• Diode parameters: peak inverse voltage, maximum forward current, temperature sensitivity, frequency, leakage current, power dissipation
• Operation and function of diodes in circuits: clippers, clampers, full-wave and half-wave rectifiers, bridge rectifiers, voltage doublers and triplers
• Detailed operation and characteristics of: Zener diode, silicon controlled rectifier (thyristor), light emitting diode, Schottky diode, photodiode, varactor diode, varistor

4.1.2Transistors

(a) Basic:

• Transistor symbols
• Component description and orientation
• Transistor characteristics and properties

(b) Detailed:

• Construction and operation of PNP and NPN transistors
• Base, collector and emitter configurations
• Testing of transistors
• Basic appreciation of other transistor types and their uses
• Application of transistors: classes of amplifier (A, B, C)
• Simple circuits including: bias, decoupling, feedback and stabilisation
• Principles of multistage circuit: cascades, push-pull, oscillators, multivibrators, flip-flop circuits
• Field effect transistors

4.1.3Integrated Circuits

(a) Basic:

• Description and operation of logic circuits and linear circuits / operational amplifiers

(b) Detailed:

• Description and operation of logic circuits and linear circuits
• Introduction to operation and function of an operational amplifier used as: integrator, differentiator, voltage follower, comparator
• Operation and use of amplifier stages: single stage, push-pull
• Advantages and disadvantages of positive and negative feedback
• Stage coupling: resistive-capacitive, inductive, inductive-capacitive, direct, transformer

4.2Printed Circuit Boards

• Description and use of printed circuit boards

4.3Servomechanisms

(a) Basic:

• Understanding of the following terms: open and closed loop systems, follow up, analogue transducers
• Principles of operation and use of the following synchro system components: resolvers, differential, control and torque, transformers, inductance transmitters and capacitance transmitters

(b) Detailed:

• Understanding of the following terms: open and closed loop systems, feedback, follow up, analogue transducers, servo loop gain, servo loop bandwidth
• Construction, operation and use of the following synchro system components: resolvers, differential, control and torque, E and I transformers, inductance transmitters, capacitance transmitters, synchronous transmitters
• Servomechanism defects, reversal of synchro leads, hunting