A motor driver is a chip that drives motors. A motor shield is a circuit board with connections on it that contains a motor driver chip that drives motors.
Do I need a motor shield for Arduino?
You don’t need this shield to drive servo motors, they have their own controller, you need just a 5V power line, GND and digital output pin to generate a PWM and that’s it. Usually Arduino has enough power to drive servo motors. This shield you are talking about is used for DC (direct current) and stepper motor.
Why are motor controllers so expensive?
Because they require different electrical systems and specific components to have accurate control from varying external disturbance. They need such as: inverter(with circuit protection), sensors, platform control.
Do all motors need drivers?
So mainly, any motor usually needs a driver circuit because its voltage/current requirements are different from the device that’s trying to control it. At a high level, a motor driver takes a “logic-level” input (desired “effort”) and delivers a corresponding “high-side” output to the motor.
How do I choose a motor driver?
As a general rule of thumb, pick a motor driver whose operating voltage range is around 1.5x to 2x that of the supply you are running the motor off.