ENGR337 Lab 2020 Spring
Lab 1: LTSpice and Lab Report Preparation
Name: Audra Benally
Email: albenally1@fortlewis.edu

1. Title: LTSpice and Lab Report Preparation

2. Introduction: The purpose of this lab is to introduce the student to the LTSpice program and to brush up on basic circuits' methods and knowledge.

3. Materials and Methods:
        Materials:
                     - Computer with LTSpice
                 - (x3) 2kΩ resistors
                 - (x3) 3kΩ resistors
                 - Breadboard
                 - Multimeter
                 - Wires
                 - 5V Voltage Source
        Methods:
                 Part 1 was the only part where the circuit was build on a breadboard and physically measured with a multimeter. Voltage was measured in parallel with the resistors. Current was measured by breaking the circuit next to the resistor (that was being measured) and connecting the multimeter in a way to complete the circuit. The calculated current was determined using the mesh current method while Ohm's Law was used to find the voltage. As for the rest of the parts, LTSpice and notepad was used to simulate the given circuits. The code was written in notepad then opened in LTSpice where the circuit was ran and traces were added to the graphs and measured using the cursorfunction.

4. Results:
     Part 1

   
                                  Figure 1. Breadboard circuit from part 1
 
                                 Table 1. Current and Voltage Data  
    
     ^^ I calculated and measured different voltages...

         
                                  Figure 2. Simulation for part 1

    Part 2:
    
                                 Figure 3. Simulation for part 2

    Part 3:

   
                                Figure 4. Part 3 simulation

    Part 4:
   
                                Figure 5. Part 4 simulation

    Part 5:
   
                        Figure 6. Part 5 simulation, time delay ~ 18.77

   
                      Figure 7. Part 5 time delay calculation

5. Discussion
The purpose of this lab was to review important methods learned in previous circuits classes. Part 1 was hands-on and helped brush up on testing and comparing separate forms of circuit analysis. The data in part 1 was very similar but not completely the same; the simulation and measured current was extraordinarily similar but the calculated was a little bit different. Variables like internal resistance and other factors due to real life may be the cause of this. One mistake made was the measurement of the voltages. The voltage across the resistor was calculated using Ohm's Law (V=IR) and measured by putting the multimeter in parallel with each resistor but the voltage of the nodes was presented in the simulation. Because I had done the calculation and measurements before the simulation I had not known that the voltage at the nodes what the measured voltage. Certain voltages can be matched up with V(1) can be compared to the voltage across R4 and V(3) is the same as R5 so it looks comparable. Other than my own human error, it can be said that LTSpice can be considered very accurate judging from this data. The LTSPice program is very impressive with its large range ofcircuit analysis capabilities.