Electricity and Electronics

Mechanical Engineering
5 ECTS; 1º Ano, 2º Semestre, 15,0 T + 30,0 PL + 15,0 TP + 3,50 OT

Lecturer
- Toni dos Santos Alves

Prerequisites
Not applicable.

Objectives
The student will be able to use the fundamental tools and concepts that are required to analyse simple electric circuits, as well as some basic electronic circuits with operational amplifiers, diodes, transistors and digital logic gates.

Program
1. DC circuits.
1.1. Constitution of matter.
1.2. Definitions; fundamental variables: electric current, voltage.
1.3. International system of units.
1.4. Types of electric current.
1.5. Resistance, resistivity, conductance and conductivity of a metallic conductor.
1.6. Measurement instruments: voltmeter, ammeter, ohmmeter.
1.7. Materials used in electricity: conductors, semiconductors and insulators.
1.8. Ohm's law.
1.9. Voltage sources and current sources.
1.10. Joule's law. Power received and supplied by a circuit element.
1.11. Kirchhoff's laws.
1.12. Association of resistors in series.
1.13. Voltage divider.
1.14. Association of resistors in parallel.
1.15. Current divider.
1.16. Analysis of simple circuits with mixed association of resistors.
1.17. Superposition theorem.
1.18. Systematic procedures for application of Kirchhoff's laws.
1.19. Source transformations.
1.20. Thévenin's theorem.
1.21. Norton's theorem.
1.22. Maximum power transfer theorem.
1.23. Wye-delta transformations.

2. Single-phase AC circuits.
2.1. Need for alternating current.
2.2. Analytic representation and vectorial representation of alternating current.
2.3. Phase shift between sinusoidal variables.
2.4. Representation of sinusoidal variables by phasors.
2.5. AC circuit elements: resistor, capacitor and inductor.
2.6. Impedance, reactance and admittance.
2.7. Active, reactive and apparent power.
2.8. Power factor.
2.9. RLC circuits.
2.10. Power factor compensation.

3. Operational Amplifier (OpAmp).
3.1. Voltages and currents at the terminals of the OpAmp.
3.2. Voltage follower.
3.3. Inverting amplifier.
3.4. Summing amplifier.
3.5. Non-inverting amplifier.
3.6. Difference amplifier.
3.7. Instrumentation amplifier.
3.8. Voltage comparator.

4. Diodes. Theory of semiconductors.
4.1. N-type and p-type semiconductors.
4.2. Junctions.
4.3. Forward bias.
4.4. Reverse bias.
4.5. Load line.
4.6. Circuits with diodes (logic gates, rectifiers, limiters).
4.7. Special-purpose diodes: zener diode (voltage regulators), Schottky diode, LED and photodiode.

5. Bipolar junction transistors (BJT).
5.1. Operation states: cut-off, active region and saturation.
5.2. Common Emitter (CE) configuration.
5.3. Bias and stabilization.
5.4. The transistor as an amplifier.
5.5. The BJT as a current source.
5.6. Main applications of transistors.
5.7. The transistor as a switch.
5.8. Phototransistor and optoelectronic isolators.

Evaluation Methodology
Continuous assessment: 5 reports from laboratory assignments with a theoretical component.
Periodic assessment: written test, exams.
Final assessment: Test or exam 50% (minimum grade 9/20), laboratory reports 50% (minimum grade 10/20).

Bibliography
- Albuquerque, R. (2006). Análise de circuitos em corrente alternada. São Paulo: Érica
- Markus, O. (2007). Circuitos Elétricos - Corrente Contínua e Corrente Alternada. São Paulo: Érica
- Alves, T. (2015). Sebenta Electricidade e Electrónica. (Vol. 1). ESTA: ESTA/IPT
- Svoboda, J. e Dorf, R. (2012). Introdução aos circuitos elétricos (8ª edição). Rio de Janeiro: LTC

Method of interaction
The course content is taught in lectures. Exercises are solved in tutorial classes. Laboratory classes are used to make and test circuits that show the application of concepts studied in the lectures and tutorials.

Software used in class
Multisim is recommended.