# Setting Up the Circuit

1,687

1

1

The following information is a single lesson in a larger project. Find more great projects here.

Lesson Overview:

Now we'll build our simple circuit!

## Step 1: Connecting Power

Start by connecting the 5V and GND pins on the Arduino to the bottom voltage rails of the breadboard.

1. Connect the 5V and GND pins on the Arduino to the voltage rails on the breadboard.

2. Continue to the next step.

## Step 2: Connect the Button

In this step, you will connect the momentary pushbutton to digital pin 2 on the Arduino.

It is helpful to use several different wire colors in the project, since there will be lot of crossing wires!

1. Add a pushbutton across the middle gap in the breadboard, near column 6.
2. Connect the left side of the button to power, and the right side of the button to digital pin 2 on the Arduino.
3. Finally, connect the right side of the button to the ground rail of the breadboard through a 10 k-ohm resistor. The resistor is used to pull the pin voltage to ground when the button is not pressed. (This is actually called a "pull-down" resistor.)
4. Continue to the next step.

## Step 3: Hook Up the 9V Battery

￼￼When using circuits with different voltages, you have to connect their ground terminals together to provide a common ground or 0 volt level.

In the simulator, use this step to attach the 9V battery to the breadboard. If you are using the Arduino kit, just plug in the red and black wires of the battery adapter. You can snap in the 9V battery right before you operate the finished circuit.

1. Plug the 9V battery (simulator) or the 9V battery adapter (kit) into the top voltage rails of the breadboard. Be sure to match the terminal color to the rail color.
2. Connect the two breadboard ground rails to each other with a wire.
3. Continue to the next step.

## Step 4: Place the Transistor

Place the transistor on the breadboard. When you attach this component, the metal tab should be facing away from you. It's already in the right orientation in the circuit simulator.

You can hover over each transistor pin in the simulator to see its label. From left to right the pins are the Gate, Drain, and Source. In this project, digital pin 9 will operate transistor gate.

1. Place the transistor on row E of the breadboard, around column 18.

2. Connect the Gate pin of the transistor (left) to digital pin 9 on the breadboard.

3. Connect the Source pin of the transistor (right) to the ground rail of the breadboard.

4. Continue to the next step.

## Step 5: Attach the Motor

Next, you will attach the motor to the circuit. The motor has color coded terminals - red and black. In this project, align the motor so that the red teriminal is connected to the positive terminal of the 9V battery, and the black terminal is connected to the transistor.

In the circuit simulator, you can place the motor above the breadboard, then extend wires directly from the red and black terminals.

1. Attach the red motor terminal to the top power rail, which is connected to the positive terminal of the battery.

2. Connect the black motor terminal to the middle pin of the transistor (the Drain). Use the picture as a guide -- it might be easier to plug the motor into the top bank of breadboard sockets, then make the rest of the connection with another wire.

3. Continue to the next step.

4. Stuck? HINT: The motor will actually work in either direction. If you switch the orientation of the wires, it will spin in the opposite direction.

## Step 6: Attach the Diode

The last component to add is the diode. The diode is a polarized component, so it only passes current in one direction. Notice that the diode component has a stripe on one end. That end is the negative terminal, or cathode.

1. Connect the cathode of the diode (stripe side) to the red motor terminal.
2. Connect the anode of the diode (no stripe) to the black motor terminal.
3. The orientation of the diode may seem backwards, and in fact, it is. The diode will help prevent any back-voltage generated by the motor from going back into your circuit. Remember, back voltage will flow in the opposite direction of the voltage that you supply.
4. Continue to the next lesson to learn how to write the pinwheel code!

Next Lesson:Writing the Code

## Recommendations

• ### Arduino Class

77,773 Enrolled

## Discussions

Please use steps, no more multyple instructables. Thanks