EE 261 – Introduction to Logic Circuits Module #1 Page 1 EE 261 – Introduction to Logic Circuits Module #1 – Analog vs. Digital Topics A.Course Overview B.Analog vs. Digital Textbook Reading Assignments  1.1 – 1.12 Practice Problems  1.5 Graded Components of this Module  1 homework, 1 discussion, 1 quiz (all online)

EE 261 – Introduction to Logic Circuits Module #1 Page 2 EE 261 – Introduction to Logic Circuits Module #1 – Analog vs. Digital What you should be able to do after this module  Describe the difference between an analog and a digital signal  Give examples of analog and digital applications

EE 261 – Introduction to Logic Circuits Module #1 Page 3 Course Overview Instructor: Brock J. LaMeres Office : 533 Cobleigh Hall Phone :(406) Web : Textbook: “Digital Design: Principles and Practices", (Required) 4th Addition John F. Wakerly, Prentice Hall, 2006 Website: ecat.montana.edu - this is the Desire 2 Learn (D2L) course management system. Requisites: Pre/Co-requisite MATH 181

EE 261 – Introduction to Logic Circuits Module #1 Page 4 Course Overview Course Plan - thereare 8 modules that will be covered in this course. - each of these modules will consists of: 1) Textbook reading assignments 2) Lecture note reading assignments 3) Video tutorials (select topics) 4) Practice Problems (ungraded, solutions provided) 5) Homework Problems (weekly, 1-3 per module, graded) 6) Discussions (weekly, 1-3 per module, graded) 7) Quiz (1 per module, graded) - There will be a comprehensive final exam at the end of the semester. - The homework, discussions, and quizzes have due dates that follow a typical 16 week semester course schedule. - You can work ahead, but you can’t fall behind!

EE 261 – Introduction to Logic Circuits Module #1 Page 5 Analog vs. Digital What is an Analog Signal? - The signal is the real information. We care about the signal's value at every moment of time. - An analog signal is a time varying signal that can take on any value across a continuous range. or - Any variable that is continuous in both time and amplitude i.e., there is information on the signal at all moments in time (no gaps) i.e., time moves forward i.e, it cannot change amplitudes instantaneously (we construct special math for these cases) Examples - sound, light, smell, a sine wave, electricity from the wall We live in an analog world. Our senses are analog.

EE 261 – Introduction to Logic Circuits Module #1 Page 6 Analog vs. Digital What is a Digital Signal? - The signal is a representation of the information. or - Representations of discrete-time signals, typically derived from analog signals. - We are not sending the actual data, just a coded description of it. The receiver will decode it and know what you meant. Examples - Morris Code - A smile or frown Since we live in an analog world, digital information must be converted back to analog in order for humans to sense it.

EE 261 – Introduction to Logic Circuits Module #1 Page 7 Analog vs. Digital Disadvantages of Analog Signals - The universe is filled with electrical noise. Thermal Noise - caused by thermal agitation of charge carriers inside an electrical conductor Shot Noise- random fluctuations in current due to the current being composed of discrete charges (electrons) - This noise can be present on all signals (analog or digital). - This is a problem for analog signals because the signal represents the real information (which now has noise on it). Advantages of Digital Signals - We can have a little noise on a digital signal and still be able to determine what the original information was. - It is easier to fabricate a functional digital circuit than an analog circuit. - We can shrink digital circuits much more than analog circuits.

EE 261 – Introduction to Logic Circuits Module #1 Page 8 Analog vs. Digital Evolution from Analog to Digital Analog Digital Photography filmpixels Musicrecords, tapesCD's, MP3'S VideoVHSDVD's, LCD's Communicationsoriginal signalcoded version