Using a Transistor to Control High Current Loads with an Arduino

Basic of Transistor

The positions of base, collector, and emitter are different between drawing a schematic symbol and connecting a real NPN transistor.

Blink control of a DC motor

Blink control of a DC motor

Use potentiometer to control the speed of a DC motor

Use potentiometer to control the speed of a DC motor

DC Motor Control with H-Bridge (Motor Driver)

Connect a DC motor with Sparkfun motor driver

Question:

The DC motor(DG02S 48:1) works fine with transistor under 13V power supply, but it becomes overheated with motor driver? I tried to add 100 ****ohm resistor which based on calculation(13V/125mA = 104 ohm, and motor itself has around 20 ohm) between power supply or motor driver or AO2 and motor, the motor can't be powered.

Use potentiometer to control the speed of a DC motor, and use switch to change the direction.

Use potentiometer to control the speed of a DC motor, and use switch to change the direction.

Stepper Motor with H-Bridge

This lab was failed.

Questions:

1. What's the sequence of wires of a stepper motor?
2. Does PWMB need to be connected?
3. Does PWM Pins on Arduino matters?