Driving Motors and Other Output Devices

January 14, 2016
For the first part of this lab we were tasked with using our Arduino board to light a Christmas light.in this lab I learned why a diode is used in this application. The diode is used to protect the relays from the back emf. I also learned that back emf is a large surge in current that rushes back from any device that has a metal coil inside and can damage unprotected components. We used a back emf suppressing diode, a Darlington transistor and our 5V power supply to light the bulb.



For the second part of this lab we used Darlington Transistor in a circuit powering a motor. in the part I learned that the Darlington transistor is much larger and can take much more than the small 2N3904 transistor. I also learned how the darlington differs from the smaller resistor in how to hook the resistor and motor up to the transistor.

For the final part of this labs we had to power the motor using our Arduino board. In this part of the lab I learned that unlike other motors, BDC motors do not require a controller to switch current in the motor windings. The small transistor from earlier in the lab isn't compatible with this so I had to use the Darlington Transistor. The code that was used to control the motor is the same ode that was use to  make the Christmas light blink.