EEL 3705 3705L Digital Logic Design

Document Sample

```					           FAMU-FSU
College of Engineering

EEL 3705 / 3705L
Digital Logic Design

Fall 2006
Instructor: Dr. Michael Frank

1/8/2010           M. Frank, EEL3705 Digital Logic, Fall 2006   1
FAMU-FSU College of Engineering

Lecture Outline
      Overview of the subject area:
   What’s Digital Logic Design all about?
      Overview of the course:
   Syllabus, policies, procedures
   Sign-in sheet, Prereq form, Blackboard,
1st assignment

1/8/2010                M. Frank, EEL3705 Digital Logic, Fall 2006   2
FAMU-FSU College of Engineering

What do we mean by
“Digital Logic Design?”
      Digital
   Using discrete physical states (e.g., on/off transistor,
high/low voltage) to represent information
      Logic
   Using the basic operations of Boole’s algebra of logic to
interpret, manipulate and process information
      Design
   To conceive, plan, analyze and construct the structure of
working systems that will meet application requirements

1/8/2010                   M. Frank, EEL3705 Digital Logic, Fall 2006   3
FAMU-FSU College of Engineering

Applications of Digital Logic Design
      All complex electronic systems today rely
heavily on components whose design and
operation is based (almost entirely) on
digital logic principles, including:
    Microprocessors and microcontrollers
   The heart of the modern computer, and also
embedded within all manner of other consumer and
industrial electronic devices
    Digital Signal Processors
   Used in cellphones, cameras, networking equipment
    FPGAs (Field-Programmable Gate Arrays)
   Used for prototyping & in a wide range of equipment
    ASICs (Application-Specific Integrated Circuits)
   Semi-custom, used in many specialized applications
1/8/2010                     M. Frank, EEL3705 Digital Logic, Fall 2006   4
FAMU-FSU College of Engineering

Electrical & Computer Engineering
and the Design of Electronic Systems
      Although electrical engineering and computer
engineering are considered different disciplines, it’s
important to always remember that any complex
electronic component includes both:
   Physical/electrical characteristics
   Such as power, current, inductance, capacitance, etc.
   And computation-related characteristics
   E.g., information content, logical function, software, protocols
      To successfully design working systems requires
multidisciplinary teams that understand and can take
care of the engineering considerations on both sides!
1/8/2010                     M. Frank, EEL3705 Digital Logic, Fall 2006           5
FAMU-FSU College of Engineering

What does a modern                                                      System-level
requirements
Digital Logic Designer do?                                                        Functional design

      Design engineering, in general,                                                        Functional or
behavioral
involves taking abstract, system-level                                                 specification
requirements, and translating them into                                                       Structural
design
ever more concrete and specific                                                        Schematic or
designs for technological artifacts.                                                     structural
specification
   Digital Logic Design is no different.
Logic design
      In modern industrial practice,                                                          Gate-Level
increasingly many of the steps of the                                     Design         Design
compiler
design process have been automated.                                                           Circuit
synthesis
   This is true for digital functions especially.                     FPGA           Transistor-level
   See e.g. resources at eda.org                                 Program           Schematics

of the “grunt work” and “heavy lifting”                              Configured      VLSI Mask Layers
FPGA
   But, the designer has to understand what                                                   Fabrication
the tools are doing in order to use them!
Physical chip
1/8/2010                       M. Frank, EEL3705 Digital Logic, Fall 2006                                        6
FAMU-FSU College of Engineering

The Basis of Digital Logic today:
The MOSFET
      Nearly all digital systems
today (2006) are based on an
electronic device called the
MOSFET
   Metal-Oxide-Semiconductor
Field-Effect Transistor
   This device is a voltage-
controlled switch
      Two basic types of FET:
   nFET: The dominant charge
carriers are electrons (negative)                                             gate
   Conducts low voltages well
   pFET: The dominant charge
carriers are holes (positive)                                   source               drain
   Conducts high voltages well
nFET icon used in schematics
1/8/2010                      M. Frank, EEL3705 Digital Logic, Fall 2006                                  7
FAMU-FSU College of Engineering

Today’s Dominant Logic Style:
CMOS
      Most logic today is done in the CMOS
(Complementary MOS) logic style                                            Vdd (PWR)
   Each logic “gate” (hardware to do a given
logic operation) is built using both nFETs
and pFETs                                                        Vin   Vout
   nFETs pull output low, pFETs pull it high
   Uses energy mainly only when switching
      Here are a simple CMOS inverter
circuit and its logic gate icon                                            Vss (GND)
   When input is high (1) output is low (0)
and vice-versa.
   This and a few other simple gates are                           in     out = ¬in
sufficient to build any digital system!

1/8/2010                      M. Frank, EEL3705 Digital Logic, Fall 2006                 8
FAMU-FSU College of Engineering

Course Overview
      Go through syllabus posted on Blackboard

1/8/2010             M. Frank, EEL3705 Digital Logic, Fall 2006   9
FAMU-FSU College of Engineering

      Sign the attendance sheet being passed
around…
      Pick up and sign a prerequisite form…
   Turn it in at the end of class
      Make sure you are enrolled on Blackboard
   Email Dr. Frank if you aren’t
      Labs begin next week!
1/8/2010                 M. Frank, EEL3705 Digital Logic, Fall 2006   10
FAMU-FSU College of Engineering

First-Day Homework Assignment
          To be completed by this Wednesday’s lecture
     No time to waste!
          The assignment is:
1. Turn in the signed course prerequisite form to Dr. Frank
   Preferably, at the end of today’s lecture
2. Ensure you are enrolled for the course on Blackboard
   Email instructor at mpf@eng.fsu.edu immediately if not