28016 - Electronics T

Course contents

Requirements/Prior knowledge

Prerequisite for the understanding of the arguments is the knowledge of the key concepts of the theory of linear electrical circuits developed in the Courses of Electrical Circuits and Electrotechnics. In particular, the student should be able to analyze the behaviour of a linear circuit both in stationary and transient conditions.

Fluent spoken and written Italian is a necessary pre-requisite: all lectures and tutorials, and all study material will be in Italian.

Course Contents

1. Introduction to the course: a brief history of Electronics, classification of electronic signals (digital, analog, A/D and D/A conversion), important concepts from circuit theory, frequency spectrum, introduction to amplifiers.
2. Physics of semiconductors: solid-state electronic materials, drift currents and mobility in semiconductors, impurities and electron and hole concentrations, resistivity, diffusion current, overview of integrated circuit fabrication.
3. Solid-state diodes and diode circuits: I-V characteristics, the diode equation, reverse and forward bias, diode temperature coefficient, pn junction capacitance, diode circuit analysis, voltage regulation, half-wave, full-wave and full-wave bridge rectifiers.
4. Field effect transistor: the MOS capacitor, the nMOS transistor, pMOS transistor, capacitances of the MOSFET, biasing of the MOSFET.
5. Bipolar junction transistors: physical structure of the bipolar transistor, the transport model of the npn transistor, the pnp transistor, equivalent circuit representation of the transport models, I-V characteristics, transport model simplifications, nonideal behavior of the bipolar transistor (junction breakdown voltage, diffusion capacitance, Early effect), transconductance, bias circuits for the BJT.
6. Analog electronic systems: amplification (voltage, current and power gain), distortion in amplifiers, two-port models for amplifiers, mismatched source and load resistances, transfer functions and frequency response.
7. Operational amplifiers: differential amplifier, ideal operational amplifier, circuits with ideal OPAMPs.
8. Nonideal operational amplifiers: feedback systems, analysis of circuits containing nonideal OPAMPs, common-mode rejection ratio, input resistance, frequency answer and bandwidth.
9. Small-signal modeling and linear amplifiers: small-signal model for the diode, small-signal model for the BJT, small-signal mdel for the MOSFET, common-source amplifier, common-emitter amplifier, examples of amplifiers and source-follower
10. Power circuits: block diagram of a power supply, AC-DC converters, linear DC-DC converters (voltage regulator, Zener-diode regulator (diode current, conditions on the biasing and load resistances), BJT regulator (input and output current, biasing resistance), OPAMP regulator, trimmer. Switching DC-DC converters: features and functioning issues. DC-DC converters with inductive load and free-wheeling diode. Buck DC-DC converter. DC/AC converters: inverters.
11. Power devices: power diode (structure and I-V characteristics, switching features), power BJT (active region, quasi-saturation regime deep saturation regime), issue of the draining of minority charge in the drift region during the switching-off, power MOSFET (vertical structure, parasitic effects, gate capacitance in saturation and ohmic region), optimization of the on resistance, biasing circuits, power MOSFET used as switch in the DC-DC converter with inductive load, IGBT (structure and functioning), IGBT switch.

Readings/Bibliography

· R. C. Jaeger e T. N. Blalock, "Microelettronica", ed. 2017, McGraw-Hill ISBN 978-88-386-1555-9

· N. Mohan, T. M. Undeland, W.P. Robbins, “Power Electronics: Converters, Applications, and Design”, Wiley

· S.B. Dewan, A. Straughen, “Power Semiconductor Circuits”, Wiley – Interscience Publication

· M.J. Fisher, “Power Electronics”, Thomson International Publishing

Teaching methods

The course consists of classroom lectures in which the basic electronic elements are presented. In particular, we will focus on the key concepts of Analog Electronics. The theoretical presentation of each topic is followed by several lectures devoted to the solution of exercises and specific problems aiming to acquire the method for analyzing and designing simple analog circuits.

Assessment methods

Learning assessment is done through a final exam that ensures acquisition of knowledge and expected skills. The student will carry out an oral test.

The oral test consists in 3 questions, one to verify the ability to analyze circuits realized with diodes, MOS transistors, BJT transistors or OPAMPs, the second covering the main theoretical instruments for the analysis of analog circuits, and a third involving the behavior of the semiconductor power devices and circuits. To obtain a passing grade, the student must demonstrate the capacity to manage the key concepts illustrated in the course program. The duration of the oral test is about 60 minutes.

To attend the exam it is required to register via Almaesami. Those who do not succeed to register by the deadline are required to promptly notify the problem at the Secretary's office.

Teaching tools

Teaching material: slides, notes and examples of exercises with solutions will be available to students via the distribution list or in https://www.unibo.it/sitoweb/susanna.reggiani/contenuti-utili

Office hours

See the website of Susanna Reggiani