Lecture 8 - 1 ECTE290 Spring 2007 Lecture 08 2 ECTE290 Part...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1 ECTE290 Spring 2007 Lecture 08 2 ECTE290 Part B (Week 8~13) ¡ Lecturer: Zengxi Pan (Stephen) ¡ SECTE, Room 35.G24B ¡ Available time: Mon 14:30~16:30, Wed 13:30~15:30 ¡ Email: [email protected] ¡ Tel: 02-4221-5498 ¡ Textbook: Principles and Applications of Electrical Engineering, 5 th Edition, by Giorgio Rizzoni ¡ Other Sources: Wikipedia, Howstaffworks 3 Topics to be covered (Week 8-13) ¡ Diode and Applications ¡ Operational Amplifiers ¡ Digital Electronics ¡ Transformers ¡ Electric Machines: Motor and Generator ¡ Transistor: Model and Analysis 4 Today: Diodes and Applications ¡ Diodes ¡ The IDEAL Diode model ¡ Constant Voltage Drop Model ¡ Zener Diodes ¡ Applications of diodes: ¡ Half Wave Rectification ¡ Battery Charger ¡ Full Wave Rectification circuits ¡ Centre tapped transformer ¡ Bridge rectifier ¡ Clamping and Limiting circuits 2 5 Semiconductors ¡ For background on this you can read Chapter 9.1, 9.2 of Rizzoni ¡ http://en.wikipedia.org/wiki/Semiconductor ¡ While this is not covered in this course, the material in Chapter 20 of Hughes can help you understand better the physics of semiconductor and how diodes and transistors are constructed. 6 The Diode ¡ Most fundamental non-linear element ¡ Two terminal device ¡ Terminology from the days of vacuum-tubes ¡ Used in Power Supplies and Voltage Limiting Circuits 7 Diodes Samples ¡ Thus far, we have mostly had linear components: Resistor, Inductor and Capacitor. ¡ Now, here we have a fundamental, nonlinear device. ¡ Diodes are like one-way valves for current. ¡ It is not only nonlinear, it is also not symmetrical. 8 Real Diodes: Diode Markings ¡ The Cathode (K) is usually marked with a silver bar ¡ Example: Cathode 3 9 Diodes are like one-way valves for current. They only conduct in one direction. This is analogous to the valves in your heart, through which blood passes in only one direction. Heart Valves allow blood to flow in only one direction. One Way Valves 10 Principle: Diodes Voltage Source V L >V R V L <V R Short circuit Open circuit 11 Ideal Diode Model: I-V Characteristics In Reverse Bias Diode is Cutoff or Simply ‘Off’ In Forward Bias Diode is turned on or Simply ‘On’ Symbol for Ideal Diode 12 Properties: Ideal Diode ¡ In an ideal diode, current flow freely through the device when forward biased, having no resistance. ¡ In an ideal diode, there would be no voltage drop across it when forward biased. All of the source voltage would be dropped across circuit resistors. ¡ In an ideal diode, when reverse biased, it would have infinite resistance, causing zero current flow. 4 13 Example: The Ideal Diode Reverse Bias All 10 volts appears across the reverse biased diode Forward Bias 1k ohm resistor determines current 14 Methodology: Solving The Ideal Diode Circuit 1. Assuming a diode conduction state....
View Full Document

This note was uploaded on 10/27/2009 for the course ECTE 290 taught by Professor Zhengli during the Three '09 term at University of Wollongong, Australia.

Page1 / 15

Lecture 8 - 1 ECTE290 Spring 2007 Lecture 08 2 ECTE290 Part...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online