Fall 2015
EE Courses Overview
Freshman
Sophomore
Physical
Physical
Training 1
Training 2
Academic
Academic
English 1
English 2
Chemistry for
Engineers
Critical
Thinking
Physics 1
Physics 2
Calculus 1
Calculus 2
Introduction
to Electrical
Engineering
22 credits
Ho Chi Minh’s
Thought
Introduction
to Computer
p
for Engineers
20 credits
Senior
RF Design
General
Elective
1 Antenna and Microwave Engineering
2 RF Circuit Design
3
4
5
6
Electronics & Embedded Systems
y
Note:
Each student has to
select six elective
courses, where two of
the elective courses are
compulsory for each
specialization.
1 Analog Electronics
2 Embedded Real-time Systems
3
4
5
Physics 3
Calculus 3
Applied Linear
Algebra
Processes
Principles of
Marxism
Junior
Physics 4
6
Wireless Communications
1 Computer & Comm.
Comm Networks
2 Telecommunication Networks
3
4
5
6
Probability
and Random
Processes
Differential
Equations
Processes
Signal Processing
Prerequisite
Co‐ requisite
Lab
Mandatory
Courses
1 Control Systems
2 Embedded
E b dd d Real-time
R l ti
S
Systems
t
3
4
5
6
Revolutionary
Lines of VCP
Programming
for Engineers
Electronics
Devices
Digital
Electronics
Principles
of EE1
Principles of
EE2
Signals &
Systems
Digital Signal
Processing
Entrepreneurship
Digital
Di
it l Logic
L i
Design
Electromagn
Electromagnetic Theory
processor
Principles of
Communications
S i
Senior
Th i
Thesis
14 credits
10 credits
23 credits
20 credits
Systems
15 credits
Summer
Internship
p
17 credits
1
Fall 2015
Introduction to
Electrical Engineering
g
g1
Textbook:
Electric Circuits
James W. Nilsson & Susan A. Riedel
9th Edition.
Link to download materials:
Blackboard of IU or
https://www.mediafire.com/folder/b4wng0vg8aovp/PrinciplesofEE1 or
htt //t
http://teachingassistanteeiu.blogspot.com/
hi
i t t i bl
t
/
2
Fall 2015
Survival Skills
To make efficient use of your time and money,
money
you should strive to attend every lecture.
Supplements might be provided during class.
class
 “Understanding” is the key.
 It’s
I ’ not just
j about
b
getting
i a ‘pass’,
‘
’ Try
T to have
h
fun while learning and practicing.
 As a IU student, take pride in yourself. Never
cheat.
3
Fall 2015
A Story
http://www.gentraco.com.vn/vn/tin-tuc/gia-gao-xuat-khau-tang-nhe.html
VN is a agricultural country
Export: ~$410/ton
Almost 1,000,000,000 transistors
Features as small as a nanometer
@ amazon.com: $322 - 408
4
Fall 2015
Moor’s Law
5
Fall 2015
6
Fall 2015
Prologue to Electronics
S9 4K UHD TV
Electronics
=
Cell phone
Laptop
Electronic
y
systems
=
Amplifiers,
A
lifi
Signal
sources,
Power
supplies, and
Digital logic
circuits
Tablets
7
Fall 2015
Prologue to Electronics (cont.)
• Electronics is defined as the science of the motion of charges
g
in a gas, vacuum, or semiconductor.
• Today, electronics generally involves transistors and transistor
circuits.
i it Microelectronics
Mi
l t i refers
f to
t integrated
i t
t d circuit
i it (IC)
technology, which can produce a circuit with multimillions of
components on a single piece of semiconductor material.
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Fall 2015
ELECTRONIC CIRCUITS
The analysis of electronic circuits is divided into two parts: one
deals with the dc input and its circuit response (amplification,
filter,..), and the other deals with the signal input and the
resulting circuit response.
9
Fall 2015
Devices in Electronic Circuits
• Passive components – cannot provide power gain
– e.g.,
e g resistor
resistor, capacitor
capacitor, inductor
• Active devices – can provide power gain and must
draw power from a supply
– e.g., Vacuum tube devices, silicon transistors
– Enable signal amplification which is a key technology
for the success of long distance telephony
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Fall 2015
Circuit theories and skills that
you MUST learn
•
•
•
•
•
•
•
•
KCL and KVL
Nodal and Mesh analysis
Linearityy and Superposition
p p
Source transformation
Thevenin and Norton theorems
Maximum power transfer
AC analysis
…
You should already be able to analyze circuits that
consist of R
R, C and LL, ii.e.,
e passive circuits
circuits.
11
Fall 2015
CHAPTER 1 – Circuit Variables
12
Fall 2015
What is an Electric Circuit?
“ A mathematical model that approximates the behavior
of an actual circuit system
system.”
Circuit theory is a special case of electromagnetic field
theory.
mathematical model
actual circuit system
13
Fall 2015
International System of Units (SI)
SI unit can be divided into two classes: base units and derived units
Base units
Derived units
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Fall 2015
Standardized prefixes to signify powers of 10
Multiple Prefixes
Sub-multiple Prefixes
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Fall 2015
Voltage (Electric) “V”
The concept of electric charge is the basis for describing all electrical
phenomena.
• The charge is bipolar: positive and negative charges.
charges
• The electric charge exists in discrete quantities, which are integral
multiples of the electronic charge, 1.6022 × 10-19 C.
In circuit theory, the separation of charge creates an
electric force (voltage), and the motion of charge
creates an electric fluid (current).
The voltage (electric) is the energy per unit charge.
v
dw
dq
J/C or (V)
16
Fall 2015
Electric Current “I”
The electrical effects caused by charges in motion depend on the
rate of charge flow. The rate of charge flow is known as the
electric
l t i current,
t which
hi h iis expressed
d as
dqq
i
dt
C/s or (A)
Thus in a current of 1 ampere, charge is being transferred
at a rate of 1 coulomb per second
17
Fall 2015
The ideal basic circuit element
• Attributes of the ideal basic circuit element:
• It has only
y two terminal
• It is described mathematically in terms of current and/or voltage
• It cannot be subdivided into other elements.
• Note:
• It is called ideal because it does not exist as a realizable physical
component.
Ideal component
realizable physical component.
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Fall 2015
Interpretation of Reference Directions
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Fall 2015
Example 1.1
No charge exists at the upper terminal of the element
in the Figure. for t < 0. At t = 0, a 5 A current begins to
fl into
flow
i t th
the upper tterminal.
i l
a) Derive the expression for the charge accumulating at the upper terminal of
the element for t > 0.
b) If the current is stopped after 10 seconds, how much charge has
accumulated at the upper terminal?
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Fall 2015
Solution
a) From the definition of current, the expression for charge accumulation
due to current flow is
Therefore,
Therefore
b) The total charge that accumulates at the upper terminal in 10
seconds due to a 5 A current is q(10) = 5(10) = 50 C.
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Fall 2015
Example 1.2
The current at the terminals of the element in Fig is:
i = 0,,
t < 0;;
i = 20e‐5000t A, t ≥ 0.
Calculate the total charge (in microcoulombs) entering the element at
its upper terminal.
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Fall 2015
Solution
Current is the time rate of change of charge, or i = dq/dt. In this problem, we
are given the current and asked to find the total charge. To do this, we must
integrate the equation to find an expression for charge in terms of currents:
We are given the expression for current, i, which can be substituted into the
above expression. To find the total charge, we let t  ∞ in the integral. Thus we
have:
23
Fall 2015
Active and Passive Elements
•
Active element is one that models a device that is capable of generating
electric energy
Example: Sources
•
Passive element is one that models a device that cannot generate electric
energy
Example: Resistors, inductors and capacitors
24
Fall 2015
Power and Energy
Power and energy calculations also are important in circuit analysis.
Power is the time rate of expanding or absorbing energy
dw  dw
d
d   dq
d 
.   vi
p
 
dt  dq   dt 
•
•
Eq. is correct if the reference direction for the
Eq
current is in the direction of the reference voltage
drop across the terminals.
If the power is positive (that is, if p > 0), power is being delivered to the circuit
inside the box.
If the power is negative (that is, if p < 0), power is being extracted from the circuit
i id the
inside
th box.
b
Figure summarizes the
relationship between the
polarity references for
voltage and current and the
expression for power.
25
Fall 2015
For example, suppose that we have selected the polarity references
shown in Fig.
g (b).
( ) Assume further that our calculations for the current
and voltage yield the following numerical results:
i = 4 A and v = ‐10 V.
Then the power associated with the terminal pair 1,2 is
p = -(-10)(4) = 40 W.
Thus the circuit inside the box is absorbing
g 40 W.
If we choose the reference polarities shown in
Fig. (c). The resulting numerical values are
i = ‐4 A, v = 10 V,
and p = 40 W.
Note that interpreting these results in terms of this reference system gives
the same conclusions that we previously obtained—namely, that the circuit
inside the box is absorbing 40 W
W.
26
Fall 2015
Example 1.4
When a car has a dead battery, it can often be started by connecting the
battery from another car across its terminals. The positive terminals are
connected together as are the negative terminals. The connection is
illustrated in the Figure. Assume the current i in the Figure is measured
and found to be 30 A.
a) Which car has the dead battery?
b) If this connection is maintained for 1 min, how much energy is
transferred to the dead battery?
27
Fall 2015
Solution
a) In car A, the current i is in the direction of the voltage drop across
the 12 V battery (the current i flows into the + terminal of the
battery of car A). Thus using the passive sign convention,
p = vi = 30 × 12 = 360 W
since the power is positive, the battery in car A is absorbing
power, so car A must have the “dead” battery.
b)
28
Fall 2015
CHAPTER 2 – Circuit Elements
There are five ideal basic circuit elements:
• resistors,
• voltage
g sources,,
• current sources,
• inductors,
inductors and
• capacitors.
29
Fall 2015
Electrical Resistance
• Resistance is the capacity of materials to holdback the flow of
current or,
or more specifically,
specifically the flow of electric charge.
charge
• The circuit element used to model this behavior is the resistor.
R
30
Fall 2015
Voltage and current sources
•
An electrical source is a device that is capable of converting non‐electric
energy to electric energy and vice versa.
Example: battery, generator, etc.
•
Ideal voltage and current sources
– An ideal voltage source is a circuit element that maintains a prescribed
voltage across its terminal regardless
dl
in those terminals.
off th
the currentt flowing
– An ideal current source is a circuit element that maintains a prescribed
current across its terminal regardless
those terminals
terminals.
of the voltage across
31
Fall 2015
Independent and dependent sources
•
An independent source establishes a voltage or current without relying on
voltage or currents elsewhere in the circuit.
•
A dependent source establishes a voltage or current whose value depends
on the value of a voltage or current elsewhere in the circuit.
Voltage source
Current source
Controlled voltage
source
Controlled current
source
32
Fall 2015
Example 2.1
Which connection is valid and which is not?
Solution?
33
Fall 2015
Ohm’s Law
It is the algebraic relationship between voltage and current for a resistor
v = iR
v = the voltage in volts
i = the
th currentt in
i amperes
R = the resistance in ohms (Ω)
34
Fall 2015
Ohm’s Law (cont.)
35
Fall 2015
Example 2.2
I each
In
h circuit
i it iin th
the Fi
Figure, either
ith th
the value
l off v or i is
i nott kknown.
a) Calculate the values of v and i.
b) Determine the power dissipated in
each resistor.
a) Va = (1)(8) = 8 V. ib = (50)(0.2) = 10 A. vc = ‐(1)(20) = ‐20 V. id = ‐ 50/25 = ‐ 2 A
36
Fall 2015
Example 2.3
37
Fall 2015
Kirchhoff’s Law
38
Fall 2015
Kirchhoff’s Law
• Kirchhoff’s Current Law (KCL)
The algebraic sum of all the currents at any node in the circuit
equals zero
• Ki
Kirchhoff’s
hh ff’ V
Voltage
lt
Law
L (KVL)
The algebraic sum of all the voltages around any close path
equals
q
zero
39
Fall 2015
Kirchhoff’s Current Law
40
Fall 2015
Kirchhoff’s Voltage Law
41
Fall 2015
Kirchhoff’s Law
42
Fall 2015
Example 2.4
Sum the currents at each node in the circuit shown in Figure
Figure. Note that there
is no connection dot (•) in the center of the diagram, where the 4  branch
crosses the branch containing the ideal current source ia.
IIn writing
iti th
the equations,
ti
we use a
positive sign for a current leaving a
node. The four equations are
43
Fall 2015
Example 2.5
Sum the
S
th voltages
lt
around
d each
hd
designated
i
t d path
th iin th
the circuit
i it shown
h
iin
Figure
In writing the equations, we use a
positive sign for a voltage drop.
The four equations are
44
Fall 2015
Example 2.6
45
Fall 2015
Example 2.6 (cont.)
KVL
46
Fall 2015
Example 2.6 (cont.)
47
Fall 2015
Circuit containing dependent sources
48
Fall 2015
Example 2.7
49
Fall 2015
Example 2.8
50
Fall 2015
Example 2.9
51
Fall 2015
Solution
52
Fall 2015
Calculate power using the formula p = Ri2:
Sum the power dissipated by the resistors:
The power associated with the sources is
Thus the total power dissipated is 1310 + 400 = 1710 W and the total power
d
developed
l
d iis 1710 W
W, so th
the power b
balances.
l
53