EE171

Electrical Engineering Department
Portland State University
Portland, OR

DESIGN PROJECT #2

Problem Description:

Continuing with Project 1, you will now simulate that circuit to determine whether your design works or not. If you find that your design does not work, you will repeat the design-simulate loop until it does. A large part of the grade for this project is based on how thoroughly and clearly you document your work.

To complete the project:

  1. Carefully work your way through Mentor Tutorial #3.
  2. Use the process described in the tutorial to apply a binary count sequence to the inputs of the circuit that you designed in Project #1. Add traces for input and output signals, and run the simulation. For this circuit, you don't need to check for hazards. If hazards or delays in output values make your waveforms difficult to read, then use longer duration periods for your input signals.
  3. Print out the results of the simulation, and carefully check to see if the results are correct for all input combinations.
  4. If the results are not correct, document the error and possible cause of it. (You may want to add probes and re-run the simulation to see logic levels on intermediate points.) Fix the problem, re-design the circuit, and then simulate it again. Repeat this step until the circuit output is correct for every input combination.

Documentation

Your documentation should consist of two separate entities, the log book and the formal report.

Log book

This is an "as you go" write up of the project. Include an ongoing record of your thought process and attempts as you test your design, with DATED ENTRIES. Include a detailed log of the steps you took to simulate and, if necessary, correct the design of the circuit.

Formal report

The formal report is a document that will be written at the end of the project. It will be done "nicely". In fact, think of this as your presentation of the project. It is suggested, but not required, that you type your report. Include the following sections in your report.
    1. Introduction - Describe the problem and your objective for the project.
    2. Simulation - Describe the simulation process and summarize your debugging steps.
    3. Final Circuit -For your final, working design only (may be the same as in Project #1 - if you are lucky!), show output expressions and a schematic of your circuit. Also include a thoroughly labeled printout of the simulation. This includes labeling all inputs/outputs. To make this readable, convert each of the 6-inputs to the Octal equivalent and if it is a LETTER or NUMBER specify that LETTER or NUMBER. Labeling the printout allows for someone else to understand the printout without looking at the rest of the document.
    4. Analysis - List the number and type of devices used in the final design. (The amount of credit given will be inversely proportional to the number of ICs required by the final design.)
    5. Conclusion - What was developed, learned, etc.
    6. Include the following signed "intellectual property" statement:

      I do hereby affirm that I designed this circuit by myself. 
    Signed __________________________________  Date _______________

To receive credit you must do this project yourself and include the signed statement!

Grading: Project 2 is worth 15 points (50 total project points)

Grade will be based 60% on quality of technical work, 40% on quality of documentation.