ENGR337 Lab 2020 Spring
Lab 5: Rectifiers and DC Regulators
Name: Audra Benally
Email: albenally1@fortlewis.edu

1. Title: Lab 5 Rectifiers and DC Regulators

2. Introduction: The goal of this study is to learn more about rectifiers and DC regulators and to build a DC power supply. This was achieved through LTSpice simulation and actual breadboards with capacitors and diodes connected in specific ways.

3. Materials and Methods:
       Materials:
          - Oscilloscope
          - Function Generator
          - Capacitors: 10µF x3 and 1µF x2
          - Resistor: 1K-Ohm
          - 1N4370 Zener Diode and 1N5767 Diodes
          - Multimeter
          - Computer with LTSpice

       Methods:
   In these following tasks diodes, capacitors, and resistors were used to build and simulate circuits. The simulation was done first in all cases so we could compare the results on the oscilloscope to the simulated graphs so we knew whether or not we built the circuit correctly.

4. Results:

  
             Figure 1. Task 1 LTSpice simulation of a diode connected in forward bias in series with a 1k-Ohm resistor.

   
             Figure 2. Task 1 simulated circuit after the built-in potential was changed to 0.6V

   
                Figure 3. Task 1 circuit on the oscilloscope. The scales are different (2V and 5V) so the blue (Vout) signal is smaller than it really is.

  
                Figure 4. Task 2 LTSPice simulation.

   
                Figure 4. Task 2 circuit V input (yellow) and V output (blue). The scales were also different in this picture so Vout is lower than it really was.

   
                Figure 5. Task 3 part 1 LTSpice simulation, the diodes connected in opposite biases in parellel with the Vin are capping the input wave in the positive and negative ranges.

   
             Figure 6. Task 3 part 1 circuit voltage input (yellow) and output (blue). The scales were different in this picture as well.

   
             Figure 7. Task 3 part 2 LTSpice simulation of Zener diodes connected in a way that caps the voltage input at a specified voltage.

   
             Figure 8. Task 3 part 2 Vout is "clamping" Vin, a method used to protect circuits against high voltages.

   
             Figure 9. Task 4 LTSpice simulation AC to DC voltage.

   
             Figure 10. Task 4 circuit DC Vout signal

5. Discussion
    In this experiment, we were able to recreate the results of the simulation in every task. It wasn't until the report was being put together that I realized we forgot to make the scale the same in several figures. This explains some confusion during the experiment. The only unclear result at the time was in Task 4 when we powered up the circuit it immediately shot up above the analog Vin signal. When the circuit was disconnected the Vout slowly went down as the capacitors discharged which made the results clearer as to what happened.