2017 Electric Circuits

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Academic unit or major
Undergraduate major in Information and Communications Engineering
Kobayashi Takao  Sugino Nobuhiko 
Class Format
Media-enhanced courses
Day/Period(Room No.)
Tue7-8(S514)  Fri7-8(S514)  
Course number
Academic year
Offered quarter
Syllabus updated
Lecture notes updated
Language used
Access Index

Course description and aims

This course focuses on analyzing electric circuits consisting of sources and linear passive circuit elements, such as resistors, capacitors, inductors, and transformers. Alternating current (AC) sources with sine waves are assumed, which include direct current (DC) sources as a special case when the frequency is set to zero. Topics include AC voltage, current, and power, phasor representation, impedance and admittance, resonant circuits, transformers, network analysis by branch current method, nodal analysis, loop analysis, useful theorems for network analysis, and 2-port networks. By combining lectures and exercises, the course enables students to understand fundamentals of AC circuit analysis.
A wide variety of electric circuits including analog and digital electronic circuits are used in the areas related information and communication technology (ICT). For designing and analyzing such electric circuits, the knowledge that provided in this course must be essential. Moreover some theorems and methods are applicable to analysis of linear electronic circuits and general linear systems. Thus students should be noted that the knowledge acquired through this course would become the basis of ICT studies.

Student learning outcomes

By the end of this course, students will be able to:
1) Understand instantaneous and effective values of physical quantities for describing AC circuits, such as voltage, current, and power, and also represent these quantities by phasors.
2) Calculate impedance and/or admittance.
3) Draw impedance locus and reactance curve of a given circuit.
4) Determine voltages and currents of a given circuit based on Kirchhoff’s laws.
5) Analyze networks by determining voltages and currents based on nodal equations and/or loop equations.
6) Represent an arbitrary circuit consisting of many sources and elements by a simple equivalent circuit.


AC sine wave, phasor, impedance, admittance, resonant circuits, nodal analysis, loop analysis, two-port network

Competencies that will be developed

Specialist skills Intercultural skills Communication skills Critical thinking skills Practical and/or problem-solving skills

Class flow

At the beginning of each class, summary of the previous class and answers to assignments are reviewed. Towards the end of class, students are given exercise problems related to what is taught on that day to solve, and also given assignments as necessary.

Course schedule/Required learning

  Course schedule Required learning
Class 1 Introduction to electric circuits: voltage, current, power Understand physical quantities that describe properties of electric circuits, such as voltage, current, and power.
Class 2 Direct current (DC) circuits: voltage and current sources, resistive circuits Understand current sources and how to analyze networks consisting of DC sources and resistors.
Class 3 Circuit elements: resistors, capacitors, inductors Understand relationship between current and voltage of basic circuit element.
Class 4 Alternating current (AC): voltage, current, power, phase, frequency Understand alternating current waveforms, especially sine waves and their parameters.
Class 5 Sine waves and phasors Represent a sine wave by a complex number, or a vector called phasor.
Class 6 AC sine waves and steady-state responses of circuits elements Understand relationship between current and voltage of basic AC circuit element.
Class 7 Impedance and admittance Determine impedance or admittance of a given AC circuit consisting of several circuit elements.
Class 8 Resonant circuits and Q factor Understand resonace phenomena, and draw impedance locus and reactance curve.
Class 9 Mutual inductance and transformers, ideal transformers Understand mutual inductance and properties of transformers.
Class 10 Kirchhoff’s laws and network analysis Understand how to analyze AC circuits consisting of several sources and elements.
Class 11 Network analysis: nodal analysis Analyze networks by determining voltage at each node based on nodal equations.
Class 12 Network analysis: loop analysis Analyze networks by determining each loop current based on loop equations.
Class 13 Network theories: linearity, superposition theorem, Thevenin’s theorem Represent an arbitrary circuit consisting of many sources and elements by a simple equivalent circuit.
Class 14 Network theories: duality, reciprocity theorem, Tellegen’s theorem, compensation theorem Understand theorems that are useful for analyzing circuits.
Class 15 Two-port networks Obtain impedance, admittance, and cascade parameters of 2-port networks.


None required. Course materials are provided during class.

Reference books, course materials, etc.

All materials used in class can be found on OCW-i.

Assessment criteria and methods

Students will be assesed on their understanding of phasor representation, impedance, and admittance, and their ability to analyze AC networks.
Students’ course scores are based on final exam (70%) and exercise problems (30%).

Related courses

  • LAS.M102 : Linear Algebra I / Recitation
  • LAS.M101 : Calculus I / Recitation
  • ICT.I207 : Linear Circuits
  • ICT.S206 : Signal and System Analysis

Prerequisites (i.e., required knowledge, skills, courses, etc.)

No prerequisites.

Contact information (e-mail and phone)    Notice : Please replace from "[at]" to "@"(half-width character).

Kobayashi, Takao: kobayashi.t.aq[at]m.titech.ac.jp
Sugino, Nobuhiko: sugino.n.aa[at]m.titech.ac.jp

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