ELECTRIC CIRCUITS ECSE2010 Spring 2003 Class 1

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ELECTRIC CIRCUITSECSE-2010Spring 2003Class 1

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ASSIGNMENTS DUE

• Today (Monday)
• Activities 1-1, 1-2, 1-3 (In Class)
• Tuesday/Wednesday
• Activities 2-1, 2-2 (In Class)
• Thursday
• Will do Experiment 1 Report Due Jan 27
• Will also introduce PSpice
• Activity 3-1 (In Class)

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Bill Jennings

• Professor, ECSE
• Former Vice Provost, Professional and Distance
  Education
• Former Chair, ECSE
• Former Vice Provost, Computing Information
  Technology
• Currently On Leave, But Teaching
• Here Mondays, Wednesdays, Thursdays

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CONTACT INFORMATION

• Office JEC 6036
• Phone [phone]
• Email jenniw_at_rpi.edu
• Office Hours
• 2-4 Wednesdays, JEC 4104 (Studio)
• In addition I will usually be in my office from
  2-4 on Mondays and Thursdays

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TEXTBOOK

• Introduction to Electric Circuits
• Richard Dorf and James Svoboda
• Has Student Resources CD
• Electronic Teaching Assistant (ETA)
• Electric Circuits Workout
• Circuit Design Lab
• Interactive Illustrations
• Will Also Use ILMs Created by the Academy for
  Electronic Media

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SUPPLEMENT

• Supplement for Spring 2003
• Activities
• Notes on Using PSpice
• Computer Projects
• Experiments
• Purchase by Next Class
• Priscilla Magilligan, JEC 6049
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• Bring to Class Every Day
• Will also need Text occasionally

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WEBSITE

• http//www.ecse.rpi.edu
• Academics
• Course Homepages
• Spring 2003-ECSE 2010
• General Information and Syllabus
• Solutions to Homework Assignments
• Sample Exams and Solutions
• Class Powerpoint Slides
• BW - 6 slides per page
• PDF Files Use Adobe Acrobat

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ELECTRIC CIRCUITS

• Section 1 Prof. Millard (Administrator)
• Monday, Tuesday, Thursday 10-12
• Section 2 Prof. Jennings
• Monday, Wednesday, Thursday, 4-6
• Section 3 Prof. Nagy
• Monday, Tuesday, Thursday, 2-4

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FORMAT

• Mini-Lectures Come Prepared
• In-Class Activities Work Together, Some Short,
  Some Long, Graded
• Experiments Start in Class, Due Later, Reports
  Required, Graded
• Computer Projects Same
• Homework Due Each Week, Graded
• Graded Papers Returned in Section 2 Slot in
  Boxes on Wall in JEC 4104

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PARTNERS/TEAMS

• Choose a Partner by Thursday
• 2-Person Teams
• Most of the Work Done by Team
• Homework, In-Class Activities, Experiments,
  Computer Projects
• BUT! Submit 2 Papers Will be separately graded
• All Exams done Separately
• 3 Exams plus Final Exam
• Work Together and Help Each Other

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GRADING

• In-Class Activities Daily 10
• Homework 14 15
• Experiments 11 15
• Computer Projects 5 10
• Exam I 10
• Exam II 10
• Exam III 10
• Final Exam 20
• 100

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GRADING

• Activities 0 5 10 points
• Homework 0 -15 points
• Experiments 0 - 15 points
• Computer Projects 0 - 10 points
• Exam I 0 - 100 points
• Exam II 0 - 100 points
• Exam III 0 - 100 points
• Final Exam 0 - 150 points

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GRADE RECORDS

• Keep Your Own Records
• Activities, Experiments
• Computer Projects, Exams
• Check With Priscilla Magilligan
• Official Record Keeper for All Sections
• JEC 6049

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FINAL GRADES

• Grades Depend on Class Statistics
• All Sections Grouped Together
• Typically
• gt 90 A
• gt 80 B (B/C set at median)
• gt 70 C
• gt 55 D

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ELECTRIC CIRCUITS

• Problem Solving Techniques
• Circuits and Other Systems
• Modeling, Analysis, Simulation, and
  Experimentation of Circuits
• Vocabulary
• Language of EEs/CSEs
• Fundamentals
• Concepts EEs/CSEs Need to Know
• Foundation for Further Courses

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COURSE STRUCTURE

• Unit I Chapters 1, 2, 3, 4, 5
• Circuit Variables and Elements
• Techniques for Analyzing Resistive Circuits
• Circuit Theorems
• Unit II Chapters 6, 7, 8, 14, 9
• Operational Amplifiers
• Circuits with Inductors and Capacitors
• Response of 1st Order Circuits
• Laplace Transforms and Techniques
• Response of 2nd Order Circuits

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COURSE STRUCTURE

• Unit III Chapters 10, 11, 12, 13
• AC Steady State Circuit Analysis
• AC Power and 3 Phase Circuits
• Frequency Response
• Unit IV Chapters 13, 14, 16
• Bode Plots
• Complete Response using Laplace Transforms
• Filter Circuits

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ANALYSIS TECHNIQUES

• Series/Parallel Reduction
• Current and Voltage Dividers
• Equivalent Resistance/Impedance
• Node/Mesh Equations
• Linearity and Superposition
• Source Conversions
• Thevenin/Norton Equivalent Circuits

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VARIABLES

• Never Solve a Real Circuit
• Solve Circuit Model
• Consider a Flashlight
• Battery, Bulb, Connections, Switch, Case
• Model for Battery Ideal Voltage Source
• Battery is a DC (Direct Current) Voltage Source
• Model for Connections Ideal Wires
• No Energy Loss
• Model for Bulb Ideal Resistor
• Linear Relationship between Current and Voltage

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MODEL FOR FLASHLIGHT
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CURRENT

• Current i Flow of Charge
• i dq/dt coulombs/sec Amps A
• Current has Magnitude and Direction
• Direction of Current Arrow Direction Positive
  Charge Would Flow
• Current Flows in a Complete Path
• Assume Direction for i Calculate i
• if i gt 0 gt Correct Assumption
• if i lt 0 gt Current Flows Other Way

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VOLTAGE

• Voltage v Electrical Potential Energy
  Difference/Unit Charge gt Potential Difference
• Potential Difference Drives Charge
• v dw/dq joules/coulomb volts V
• Must define positive () and negative (-)
  terminals for voltage
• Will use passive/active conventions to do this
• Assume polarity for v If v lt 0 gt terminals are
  reversed

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POWER

• Power p Electrical Energy/Time
• p dw/dt dw/dq x dq/dt v x i
• Units of p joules/sec watts W
• Will use both Active and Passive Devices
• Passive Devices Absorb Power
• Active Devices MAY Supply Power

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ENERGY

• Energy w Electrical Energy
• Units of w watt-sec (commonly kW-hr)
• Energy may be Absorbed or Supplied
• Passive Devices Absorb Energy
• Active Devices MAY Supply Energy
• Will use Power more frequently than Energy

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UNITS
i v p 1012 Tera
TA TV TW 109 Giga GA GV
GW 106 Mega MA MV MW 103 kilo
kA kV kW 100 A V
W 10-3 milli mA mV mW 10-6 micro
uA uV uW 10-9 nano nA nV
nW 10-12 pico pA pV pW
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CONSISTENT SETS OF UNITS
i v p A V W mA V mW
A mV mW uA kV mW etc.
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PASSIVE CONVENTION

• Passive Element Absorbs Energy
• Gets Hot Power Absorbed gt 0
• Passive Element is called a LOAD
• i Flows from to - in Passive Element
• Assume Polarity for v
• Determines Direction of i in Passive Element
• OR Assume Direction for i
• Determines Polarity of v in Passive Element
• i and v will have same sign
• p v x i gt 0 Power Absorbed

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PASSIVE CONVENTION
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ACTIVE CONVENTION

• Active Element MAY Supply Energy
• Active Element is called a SOURCE
• If only 1 Source it MUST supply energy
• If more than 1 Source some may supply energy
  some may absorb energy
• i Flows from - to for Active Element
• p v x i gt 0 gt Power Supplied
• Power Supplied Power Absorbed
• In any Circuit

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ACTIVE CONVENTION
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CIRCUIT
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ACTIVITY 1-1
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ACTIVITY 1-1

• A Positive Current Flows from to -
• A Must be a Passive Element gt LOAD
• B Positive Current Flows from - to
• B Must be an Active Element gt SOURCE
• Power Supplied p v x i
• p 5000 volts x 4 microamps 20 mWatts

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IDEAL VOLTAGE SOURCE
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IDEAL VOLTAGE SOURCE
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IDEAL CURRENT SOURCE
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IDEAL CURRENT SOURCE
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IDEAL SOURCES

• Ideal Voltage Source
• Model Circle with and - voltage terminals
• Voltage always the same across voltage source
• Can supply any current
• Current through voltage source can be anything
• Ideal Current Source
• Model Circle with Current Arrow
• Current always the same from current source
• Can supply any voltage
• Voltage across current source can be anything
  

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ACTIVITY 1-2

• Circuit Elements are usually characterized by
  Device Curve
• Plot of v vs. i OR i vs. v
• Which One is an Ideal Voltage Source?
• Device 3 A Negative Voltage Source
• Which One is an Ideal Current Source?
• Device 5 A Positive Current Source

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ACTIVITY 1-2

• Which One is a Passive Device?
• Passive Device must have p gt 0 p v i
• Device 2 is a Passive Device
• Non-linear Passive Device
• Which Ones are Active Devices?
• Active Device can have p gt 0 or p lt 0
• Device 1 Device 4 Device 6

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RESISTORS

• Resistor is the Most Common Passive Element Used
  in Circuits
• Symbol R
• Circuit Model

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OHMS LAW
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OHMS LAW
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OHMS LAW

• Important Concept - Will Always Use
• Plot of v vs. i for Resistor is LINEAR
• Goes through v 0, i 0
• Slope of Line v/i R
• Units of R Ohms volts/amp
• Equation of Straight Line Thru Origin
• gt v i R
• gt Ohms Law

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OHMS LAW
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ACTIVITY 1-3
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ACTIVITY 1-3

• 1-3a
• i 12 V/3k 4 mA
• p 12 V x 4 mA 48 mW v i v2/R i2 R
• 1.3b
• i - 0.5mA gt v must be negative
• v i R - 0.5mA x 4 Mohms - 2 kV
• p v i v2/R i2 R 1 W