1. Lectures 1 and 2: Welcome to IEE
A practical introduction to Electrical, Computer and Systems, and Electric Power Engineering Concepts
Beginning with Voltage, Current, Resistance, Power, & Diodes
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

2. Introduction to Engineering Electronics
Prof. K. A. Connor
Office: JEC 6010
Phone: 8552
Secretary: Audrey Hayner in JEC 6003
Info on WebCT – Go to
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

3. Introduction to Engineering Electronics
Course Organization
Lectures each Monday on a range of topics involving the use of electronics and other fundamental concepts in engineering, particularly in Electrical, Computer and Systems, and Electric Power Engineering
10-11 Labs
Homework (Not very much)
All work must be completed in a timely manner to pass. (S/U grade)
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

4. Introduction to Engineering Electronics
Requirements
All lectures are mandatory
Attendance is taken through a variety of activities
Up to 2 unexcused absences are permitted
All labs are mandatory
Make up time is provided should a lab be missed
Missed labs must be completed promptly. You cannot be more than one lab behind at any time.
Signed rules statement is required
Please read syllabus (online) for policy details
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

5. Voltage, Current, Power and Resistance
Fundamental concepts
Voltage V volt
Current I amp
Power W watt
Resistance R ohm V I
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

6. Introduction to Engineering Electronics
Voltage
Voltage is defined as the amount of work done or the energy required (in joules) in moving a unit of positive charge (1 coulomb) from a lower potential to a higher potential. Voltage is also called potential difference (PD). When you measure voltage you must have two points to compare, one of them being the reference point. When measuring the voltage drop for a circuit component it is sometimes called measuring the potential across that component.
1 volt = 1 joule/coulomb
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

7. Introduction to Engineering Electronics
Voltage
Voltage is analogous to pressure. A battery in an electrical circuit plays the same role as a pump in a water system.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

8. Introduction to Engineering Electronics
Current
Current is the amount of electric charge (coulombs) flowing past a specific point in a conductor over an interval of one second. 
1 ampere = 1 coulomb/second
Electron flow is from a lower potential (voltage) to a higher potential (voltage).
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

9. Introduction to Engineering Electronics
Current
For historical reasons, current is conventionally thought to flow from the positive to the negative potential in a circuit.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

10. Introduction to Engineering Electronics
Power
Power is the rate at which energy is generated or dissipated in an electrical element.
1 watt = 1 joule/sec
Generated
Dissipated
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

11. Introduction to Engineering Electronics
Resistance
Charges passing through any conducting medium collide with the material at an extremely high rate and, thus, experience friction.
The rate at which energy is lost depends on the wire thickness (area), length and physical parameters like density and temperature as reflected through the resistivity
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

12. Introduction to Engineering Electronics
Circuit Diagram
Water flow analogy is helpful, if not totally accurate
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

13. Introduction to Engineering Electronics
Basic Electrical Laws
Ohm’s Law
Kirchoff’s Voltage Law
Kirchoff’s Current Law
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

14. Introduction to Engineering Electronics
Ohm’s Law
Georg Ohm
There is a simple linear relationship between voltage, current and resistance.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

15. Kirchoff’s Voltage Law (KVL)
Gustav Kirchoff
The sum of the voltage differences around a circuit is equal to zero.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

16. Kirchoff’s Current Law (KCL)
Applying conservation of current.
The sum of all the currents entering or exiting a node is equal to zero.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

17. Introduction to Engineering Electronics
Conservation Laws
Both the KVL and KCL are based on conservation laws.
KVL conserves voltage
KCL conserves current
Other conservation laws we know about
Conservation of energy
Conservation of momentum
A key to understanding any system is identifying the relevant conservation laws
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

18. Series Combination of Resistors
Resistors add in series
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

19. Series Combination of Resistors
The effect of resistors in series is additive. There is a corresponding voltage drop across each resistor.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

20. Parallel Combination of Resistors
The reciprocal or inverse of resistors add in parallel.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

21. Parallel Combination of Resistors
For resistors in parallel, the same voltage occurs across each resistor and more than one path exists for the current, which lowers the net resistance.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

22. Series Combination of Resistors
KVL:
Ohm’s Law:
Solve for Ia:
In General
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

23. Parallel Combination of Resistors
KCL:
Ohm’s Law:
In General:
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

24. Combination of Resistors
Series
Parallel
For two resistors, the second expression can be written as
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

25. Combination of Resistors
Adding resistors in series always results in a larger resistance than any of the individual resistors
Adding resistors in parallel always results in a smaller resistance than any of the individual resistors
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

26. Introduction to Engineering Electronics
Diodes
A diode can be considered to be an electrical one-way valve.
They are made from a large variety of materials including silicon, germanium, gallium arsenide, silicon carbide …
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

27. Introduction to Engineering Electronics
Diodes
In effect, diodes act like a flapper valve
Note: this is the simplest possible model of a diode
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

28. Introduction to Engineering Electronics
Diodes
For the flapper valve, a small positive pressure is required to open.
Likewise, for a diode, a small positive voltage is required to turn it on. This voltage is like the voltage required to power some electrical device. It is used up turning the device on so the voltages at the two ends of the diode will differ.
The voltage required to turn on a diode is typically around volt for a standard silicon diode and a few volts for a light emitting diode (LED)
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

29. Introduction to Engineering Electronics
Diodes
10 volt sinusoidal voltage source
Connect to a resistive load through a diode
This combination is called a half-wave rectifier
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

30. Introduction to Engineering Electronics
Diodes
Sinusoidal Voltage
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

31. Introduction to Engineering Electronics
Diodes
Half-wave rectifier
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

32. Introduction to Engineering Electronics
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

33. Introduction to Engineering Electronics
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

34. Introduction to Engineering Electronics
At the junction, free electrons from the N-type material fill holes from the P-type material. This creates an insulating layer in the middle of the diode called the depletion zone.
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

35. Introduction to Engineering Electronics
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

36. Introduction to Engineering Electronics
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

37. Diode V-I Characteristic
For ideal diode, current flows only one way
Real diode is close to ideal
Ideal Diode
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

38. Introduction to Engineering Electronics
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor

39. Where Will You See These Concepts Again?
In later labs in this course
V, I, R, Kirchoff’s Laws, Combining Resistors: ECSE-2010 Electric Circuits
Diode and Transistor Theory and Electronic Design: ECSE-2050 Analog Electronics, ECSE-2060 Digital Electronics and ECSE-2210 Microelectronics Technology
18 November November 2018
Introduction to Engineering Electronics
K. A. Connor