EE 2006 Electric Circuit Analysis Spring January 21, 2015 Lecture 01

Transcription

1 EE 2006 Electric Circuit Analysis Spring 2015 January 21, 2015 Lecture 01

2 Lecture Outline Course Introduction Lab information Basic concepts: charge, current, voltage 2

3 Instructor: Jing Bai Associate Professor in ECE/EE at UMD (Aug, 2007 ) Education Ph. D. Georgia Institute of Technology, Atlanta, GA, 2007 M. S. Georgia Institute of Technology, Atlanta, GA, 2003 B. Eng. Tsinghua University, Beijing, P. R. China,1996 Research Interests Optoelectronics Semiconductor micro- and nano- structures Nanostructured device for medical applications Contact jingbai@d.umn.edu, Phone: (218) , Office: MWAH 255 Webpage: Office hours: 11:00-12:00, Monday and Wednesday, or by appointment 3

4 Lab TAs Lab Sessions: Sec. 5, Monday, 4:00-7:00PM, MWAH 391 Sec. 6, Wednesday, 4:00-7:00PM, MWAH 391 Lab TA: Sandhya R Nadipalli for both sessions Office: MWAH 291 Office hours: 2-3, Wednesday and Friday 4

5 Course Information Textbook Fundamentals of Electric Circuit, 5th Edition, by Alexandar & Sadiku, McGraw-Hill, 2012 Course Assessment Homework: 7% Quizzes: 5% Labs: 20% Two midterms: 20% each Final: 25% Attendance: 3% (beyond three absences, no point) 5

6 Administrative Issues Lab security Number code Do not share with others, not even ECE student! Homework and lab reports Homework due date will be posted when assigned Lab reports are due the week following the lab exercise at the beginning of the lab section (group data, individual report!) Total 3 late days are allotted for each homework or lab report 10% of the score will be deducted for each late day Attendance Class attendance sign-in is required Lab attendance will be a portion of lab grading Re-schedule of lab session is not allowed! Exception is made only for justified reasons and must have my pre-approval Pre-lab Must be completed before the starting of lab session Account for a portion of lab report grading 6

7 Lab Safety (1) CONTACT WITH ELECTRIC CURRENT CAN CAUSE DEATH! As little as 100 ma (0.1 A) of electric current can kill, if it travels across the heart Follow instructions, ask for clarification Know where safety equipment is located - fire extinguishers, telephones, fire blankets, eye wash stations, etc. Always assume an electric circuit is hot (energized) and dangerous and act accordingly Keep work areas clean and uncluttered Double check circuit wiring before energizing Never work alone Wire with one hand - minimizes exposure to the Heart 7

8 Lab Safety (2) Always understand the laboratory procedures before touching anything. Always assume that electric circuits are potentially live and dangerous. Make sure there are adequate life saving resources available and know how to use them 8

9 Basics of Breadboard 9

10 Topic Covered Basic laws of circuits Analysis methods Circuit theorems Operational amplifiers Energy storage in capacitors and inductors First-order and second-order circuits AC circuits and power analysis 10

11 Overview Op Amps Components Voltage Power i Current Analysis AC DC H(s) Math Models 11

12 Overview on History of Electricity (1) 600 BC Ancient Greeks rub amber on cat fur to produce static charge Circa 0 AD Persians in present-day Iraq invent the battery 1720 s Stephen Gray shows that static charges can be conducted from point to point 1750 s Benjamin Franklin s One Fluid Theory of Electricity 1800 s Alessandro Volta re-invented battery by making a voltaic pile using zinc and copper disks submersed in an electrolytic solution 12

13 Overview on History of Electricity (2) 1820 s Hans Oerstad discovers electromagnetism with his famous compass and current-carrying wire experiments Andre-Marie Ampere defines electric current and electromagnetism, invents the ammeter Georg Ohm delivers his theory of electricity, including what later became Ohm s Law 1830 s Michael Faraday enters the game and things get intense 13

14 Basic Concepts Charge & current Voltage Power and energy Circuit elements 14

15 Electric Charge (1) Two types of charge Positive charge Properties Negative charge Fundamental characteristics Charge is never created nor destroyed conserved Charge always comes in an integral multiple of a basic unit e = Х C 15

16 Electric Charge (2) State of Charge Static charge: net charge, rub the balloon on hair Mobile charge: flow of charge Current 16

17 Electric Current (1) Created by motion of charge I Measured by charge change rate, unit in A (amperes) i = dq dt, 1A = 1C 1s Convention on direction: flow direction of positive charges, opposite to the flow of negative charges 17

18 Electric Current (2) Direct current (DC) Alternating current (AC) I i DC ( I ): current that remains constant with time AC ( i ): current that varies sinusoidally with time 18