Fall Training Project 8

Materials Needed 

1. For this project, you will be using the TinkerCAD software since you don’t have a voltage regulator in your Arduino kit.

2. You will need: an power supply (looks like a rectangle with knobs on it), a voltage regulator, a resistor, 2 multimeters (to see how the circuit behaves), a breadboard, and an LED

Steps 

1. Let’s start off with a breadboard, and a power supply next to it.

2. Connect the red (positive) part of the power supply to the row of holes next to the red line.

3. Connect the black (negative) part of the power supply to the row of holes next to the black line.

4. Next, take a 3.3v regulator (you can search it up in the search bar to find it) and place it so that 3 of the pins each have their own column of holes.

5. Then, place a resistor with around 330 ohms of resistance, with one end connected to the column of holes that is connected to the middle pin of the voltage regulator (also called output). The other end of the resistor should be connected to an empty column of holes.

6. Next, place an LED so that the anode (longer leg) connects to the column of holes that has the resistor connected to it (not the same column that has the middle pin of the voltage regulator though).

7. The other leg of the LED should be connected to an empty column at this point.

8. Now, connect the column of holes that are connected to the cathode of the LED (shorter leg) to the row of holes next to the black line.

1. Next, connect the column with the rightmost pin of the voltage regulator connected to it (called input) to the row of holes next to the red line.

10. Now, connect the column with the left most pin of the voltage regulator connected to it (called ground) to the row of holes next to the black line.

11. Use a multimeter and connect the red part of it to the anode (longer leg) of the LED, and the black part of it to the cathode (shorter leg).

12. Then, use another multimeter and connect the red part of it to the right side (should be the side that is connected to the middle pin of the voltage regulator).

13. The black part of the multimeter should be connected to the other side of the resistor.

14. No code is required, all you have to do now is run the simulation, and turn the knob next to the voltage reading around and see what happens.

15. Pay close attention to how constant the voltage readings are for the multimeters when you turn the knob of the power supply above 7 volts.

Explanation of how it works 

1. What a voltage regulator does is regulate the voltage that passes through it so that the output is a fixed voltage.

2. In this instance, we used a 3.3v regulator. This means that any voltage that is higher than that will be turned into 3.3v once it passes through the voltage regulator, with the remainder converted to heat.

3. After it gets turned into 3.3v, you used a resistor to limit the current going into the LED. So, since the voltage stays the same, and we limit the current to the right amount, any voltage from the power supply will light the LED up, but not burn it out.

4. There is a catch however. That is, there is a maximum voltage that the power supply can take in and a maximum amount of heat it can dissipate. Too much and it basically stops working, as there is too much power (voltage*current), making the regulator too hot.