Lecture 13 basic circuit theory i
1 / 43

Lecture 13: Basic Circuit Theory I - PowerPoint PPT Presentation

  • Uploaded on

Lecture 13: Basic Circuit Theory I. EEN 112: Introduction to Electrical and Computer Engineering. Professor Eric Rozier, 4/1/ 13. QUIZ GRADES AND RESULTS. Quiz III Grade Distribution. Grade Distribution. REVIEW. Identify the Architecture. Program Memory Data Memory. CPU. Bus.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Lecture 13: Basic Circuit Theory I' - zoey

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Lecture 13 basic circuit theory i

Lecture 13: Basic Circuit Theory I

EEN 112: Introduction to Electrical and Computer Engineering

Professor Eric Rozier, 4/1/13

Identify the architecture
Identify the Architecture






Identify the architecture1
Identify the Architecture








  • Nonvolatile memory?

  • Volatile memory?


  • Nonvolatile memory?

    • Retains stored information even when unpowered

    • Long-term or persistent storage

  • Volatile memory?

    • Requires constant power for storage

    • Information is lost when the power supply is off or interrupted

    • Temporary memory

What is a microprocessor1
What is a Microprocessor?

  • Single chip that contains the whole CPU

    • Fetches, decodes, and executes instructions stored in memory

    • Can access memory, I/O, and peripherals

What is a microcontroller1
What is a Microcontroller?

  • Microprocessor + on-chip memories and I/O devices

  • “Computer-on-a-chip”

    • Contains the CPU

    • Memory

    • Some I/O and peripherals

What is an embedded system1
What is an Embedded System?

  • Special purpose computer system, usually completely inside a device it is designed to control

  • Works to help solve specific problems, and perform pre-defined tasks

  • Usually contains inputs (sensors), a microcontroller, and outputs (actuators and indicators)

Midterm ii
Midterm II

  • Midterm II, this Wednesday!

  • Covered topics

    • Signal Processing (Quiz II, and lectures online)

    • Microprocessors/Microcontrollers (Quiz III, and lectures online)

    • PBASIC Programming (last lecture, online)


  • Smallest part of an element.

  • Nucleus surrounded by “orbiting” electrons

    • Protons – positive charge

    • Neutrons – no charge

    • Electrons – negative charge

Electron configurations
Electron Configurations

  • Electrons move independently in an orbital, an average field wave function

Electron configurations1
Electron Configurations

  • Arranged in electron shells

    • Shells contain fixed numbers of electrons

      • 1st shell – 2 electrons

      • 2nd shell – 8 electrons

      • 3rd shell – 18 electrons

      • 4th shell – 32 electrons

      • etc

Electron configurations2
Electron Configurations

  • 14 protons, 14 neutrons, 14 electrons

  • 1st shell – 2/2 electrons

  • 2nd shell – 8/8 electrons

  • 3rd shell – 2/18 electrons

Electron configurations3
Electron Configurations

  • Electrons in the outermost shell are known as valence electrons

  • When valence electrons gain sufficient energy, they can break away and become free electrons.

    • Free electrons can drift from one atom to another

    • Free electrons make electrical current possible

Free electrons
Free Electrons

  • The number of free electrons in a material allow it to be classified

    • Conductors

      • allow current to flow easily

      • large numbers of free electrons

      • Examples: silver, copper, gold

Free electrons1
Free Electrons

  • The number of free electrons in a material allow it to be classified

    • Conductors

    • Semiconductors

      • less free electrons

      • unique characteristics, basis for modern electronics

      • Examples: silicon, germanium

Free electrons2
Free Electrons

  • The number of free electrons in a material allow it to be classified

    • Conductors

    • Semiconductors

    • Insulators

      • very small number of free electrons

      • poor conductors

      • Examples: ceramics, rubber, air, dry paper

Electric charge q
Electric Charge (Q)

  • Two types of charges, positive and negative

  • Q – the electrical charge

    • Units in Coulombs (C)

  • One electron has a charge of 1.6*10^(-19) C

  • In 1 Coluomb there are 6.25*10^18 electrons


  • Rate of flow of electrons through a circuit

  • Symbol is I, measured in Amperes (or Amps)

  • The flow of on coulomb/second is one Amp


  • Related to potential energy

  • Measured between two points

    • One of those points is “ground”, a reference level to which all voltages are compared

    • If a pin is at 5V, it is measured at 5V with respect to ground


  • Voltage and current related by resistance

  • When voltage is applied to an electrical system, current begins to flow

    • Level of current is determined by resistance of the system


  • Resistance value in an electrical circuit is given in Ohms, and represented by R

Ohm s law
Ohm’s Law

  • Ohm’s Law – The amountof current (I) that will flow isproportional to the voltage(V) applied, and inverselyproportional to theresistance (R) of the circuit

  • I = V/R

    As resistance increases, current decreases

Hydraulic analogy
Hydraulic Analogy

  • Consider the diagram, when the valve is released, what will happen?

Hydraulic analogy1
Hydraulic Analogy

  • Flow rate (I) dependent on:

  • (V) pressure of thetanks

  • Restriction (R) offlow from the valve


  • Batteries feature surplus electrons on one side, and a deficiency of electrons on the other side (holes)

Power p
Power (P)

  • Power measures the rate of energy conversion

  • For a simple direct current (DC) system, it measures the rate at which electrical energy is converted into heat by power-dissipating resistive elements

Power p1
Power (P)

  • Lightbulbs convert electrical energy into heat and light

    • Unit for electrical power is familiar in this context

    • The Watt

    • P = V I

  • Using Ohm’s law and the power equation…

    • P = V I = V^2/R = I^2 R

Wrap up
Wrap Up

  • Exam next class

  • Quiz III corrections due next Monday