||Electronics and Digital Systems
Instance: 2011/2012 - 2S
Cycles of Study/Courses
Teaching Staff - Responsibilities
Teaching - Hours
This course aims to endow students with solid knowledge (CDIO Syllabus 1.1, 1.2 and 1.3) on:
- Application of laws and fundamental principles of the circuit theory (Kirchoff, overlapping, Thévenin, Norton, absorption) and the control of notions such as independent source, equivalent resistance and controlled source.
- Functioning of simple RC circuits, low pass and high pass circuits, calculation of time constants and sinusoidal and square wave responses.
- Linear amplifiers models and calculation of voltage and current gains, input and output resistance.
- Principles of p-n junction, junction diodes, bipolar transistors and field effect.
- Simple rectifier circuits
- Polarisation of electronic devices and functioning of small signals; linear approximation and equivalent models to small signals.
- Understanding the separation between AC and DC circuits. Decomposition of circuits in models for polarisation and signal.
- Configuration of common source, common drain and common gate
- Amplifier circuits with more than one transistor
- Feedback (only for automation and energy)
This course also aims to develop students’ personal and professional attitudes concerning engineering reasoning and problem solving (CDIO Syllabus 2.1- from 2.1.1 to 2.1.4) and be capable of experimenting (CDIO 2.2) and developing system thinking.
Chapter I- INTRODUCTION TO AMPLIFIERS
1. Introduction to Electronics
1.1 Signals and signal frequency spectrum
1.2 Analogue and digital signals
Signal amplification and symbols
Voltage, current and power gain
Power suppliers and amplifier saturation
Non-linear characteristics and polarisation
1.4 Amplifiers circuits
Current amplifiers and cascaded amplifiers
Types of amplifiers and relation between models
1.5 Amplifiers response
Frequency and bandwidth response measurement
Calculation of amplifier frequency response
2. Operational amplifiers
2.1 Ideal op-amp
Model, functioning and ideal characteristics
Signal in common and differential mode
2.2 Inverse configuration
Closed-loop gain and effect of finite gain
Input and output resistances
2.3 Non-inverse configuration
Closed-loop gain and effect of finite gain
Input and output resistances
2.4 Effect of finite gain and bandwidth in the behaviour of open and closed loop
2.5 Operations with large signals
Limits of tension and voltage
2.6 DC imperfections: offset tension and voltage and polarisation currents
Chapter II- DIODES AND DIODE CIRCUITS
3.1 Ideal diode
Rectifier and logic gate
3.2 Diode: valve and junction
3.3 Terminal characteristics of diodes and junctions
Direct and inverse polarisation; Breakdown
3.4 Diode conduction
Exponential model and graphic analysis
Linear parts model and constant voltage model
Ideal model and signal functioning
3.5 Operations with inverse polarisation
Breakdown operation: Zener diode
Zener diode model and temperature effects
3.6 Rectifier circuits
Half-wave and full wave rectifier; bridge rectifier
3.6 Limiting circuit and “clamping”
4. Diode physic operation
4.1 Basic concepts of semiconductors
4.2 Pn junction
Open circuit junction and junction under inverse polarisation
Junction under direct polarisation
4.3 Special diodes
Schottky, varactors, photodiodes and LEDs
Chapter III- STRUCTURE PHYSICAL OPERATION OF TRANSISTORS
5. Field effect transistors (FETs and MOSFETs)
5.1 J-FET: structure and operation
5.2 MOSFET: structure and operation
Creation of the channel and conduction
Drain-gate voltage application
Derivation of ID/VDS relationship
MOSFET channel n and p; Complementary MOS (CMOS)
5.3 Voltage tension characteristics
ID/VDS symbols and characteristics
Temperature effects and breakdown protection
5.4 CC operation
5.5 MOSFET as an amplifier
Great signals operation and graphic analysis
Operation as commuter and an amplifier
Analytical expression of transference characteristics
5.6 MOS circuits polarisation
VGS and RS
Constant source current
5.7 Operation with small signals
Polarisation point and signal drain current
Separation between DC functioning and signal
Equivalent model for signals
Gm and T model; body effect
5.8 Depletion MOSFET
6. Bipolar transistors
6.1 Structure and operation
Ways of operation
BJT npn in active mode
Real structure and Ebers-Moll model: saturation
6.2 Current voltage characteristics
Symbols, characteristics and graphical representation
Common emitter: characteristics
6.3 BJT as an amplifier
Operations with great signals
Sedra, Adel S.; Microelectronic circuits
. ISBN: 0-19-511690-9
Franclim Ferreira, Guedes de Oliveira e Vítor Tavares; Amplificadores Diferenciais e Multiandar
Teaching methods and learning activities
Theoretical classes will be based on the presentation of the themes of the course and (many) examples will be given. Besides, they will also be based on the demonstration of analysis techniques and circuit synthesis, as well as on problem solving. Theoretical classes aim to deepen students’ knowledge, rather than giving an exhaustive presentation of all of the themes. The most important information for this course is described on “Microelectric Circuits”.
In laboratory classes 4 assignment will be carried out. They will be based on basic components and their application on circuits, their assembly and testing. Students will have access to the guidelines (available on the course page). Each assignment will comprise 4 components:
1. An expositive part related to the theme of the assignment;
2. An introduction to the laboratory work;
3. A part in which students will have to work alone. They will have to finish their tasks and answer to questions.
4. Assessment of the assignment and learning outcomes.
Since this course is designed for Telecommunication, Automation and Energy students, theoretical classes will be different at the end of the semester. That means that they will be focused on the teaching of feedback.
Theoretical exams will be different because of this variation of the program.
However, laboratory classes will be similar for all areas, as well as its assessment.
Distributed evaluation with final exam
Eligibility for exams
- Students have to attend to the laboratory classes. They can only miss a certain numbers of classes (according to the rules).
- If students miss an assignment and even if they adequately justify their absence, they will have to perform that assignment during another class or outside of class. However, students have to be authorized by the professor and be supervised by the laboratory responsible.
- Students can only attend the exam, if they achieve a minimum grade of 8 out of 20 in the laboratory classes’ component.
Calculation formula of final grade
Ordinary students who are attending this course for the first time:
Laboratory component- 30%; each mini-test: 10%; final exam- 50%
Ordinary students who are attending this course for the first time, and who missed (adequately justified absence) a mini-test, the percentage of the mini-test will be added to the final exam.
Students with a special status or who attended this course in previous years, and did not ask to attend to the mini-test will be assessed in the following way:
Laboratory component (already obtained) - 30%; final exam- 70%
The mark of the laboratory component (from 0 to 20) is limited to the mark of the final exam plus 4 values.
Examinations or Special Assignments
It will take place two mini-test. The first will be between the 5th and the 6th week and the second between the 9th and 10th week of the semester. Their worth is 10% on the final mark.
Students will be assessed on their performance and participation in the laboratory classes, by answering oral questions at the end of each assignment. Laboratories will be available two more hours per week (besides class time), so that students can finish their assignments.
Laboratory classes’ component is worth 30% of the final mark.
Special assessment (TE, DA, ...)
Laboratory classes’ component is mandatory to all students. Students with a special status will also have a chance to do the assignments.
Even though they can attend to the mini-tests, they do not need to do it.
They will be assessed in the following way:
Laboratory component- 30%; each mini-test- 10%; final exam- from 50% to 70%, depending on whether students had attend to the mini-tests or not.
- Continuous assessment component mark will be the same either for the normal exam and recurso exam.
- Students who want to improve their mark in the year they attended to classes, the rules will be the same as for the recurso exam. If students want to improve their mark in following years, laboratory component is worth 30% and the exam 70%.