If you are looking for the Chapter 4 content for the 1st Edition of Exploring Arduino, please click here.

Using Transistors and Driving DC Motors

Parts List

• Arduino Uno or Adafruit METRO 328
• USB cable (Type A to B for Uno, Type A to Micro-B for METRO)
• Half-size or full-size breadboard
• Assorted jumper wires
• 1kΩ resistor
• 10kΩ resistors (×2)
• 10kΩ trim potentiometer
• Photoresistors (×2)
• 9V battery
• 9V battery clip
• L7805CV 5V voltage regulator
• 10μF 50V electrolytic capacitors (×2)
• 0.1μF ceramic capacitor
• 1N4001 diode
• PN2222 NPN bipolar junction transistor (BJT)
• Roving robot chassis kit with wheels and DC motors
• 9V DC motor
• TI L293D dual H-bridge motor driver

Code

Download Code (2nd Edition, Chapter 4)
(Also available on GitHub)

Useful Links

• L7805CV voltage regulator Datasheet (PDF)
• TI L293D H-Bridge Datasheet (PDF)
• PN2222 Datasheet (PDF)

Videos

Follow along with this video for a visual tutorial on motors and transistors:

Watch a demo of the “Roving Robot” project from this chapter: