Stepper Driver: Miniature Stepper Motor motor driver 0-2 amps per phase output current Chopper constant current Mini Stepper Motor motor driver0-2 amps per phase output currentChopper constant currentUsed in textile machines or pharmaceutical machines to drive stepper motors

Advantages: The primary advantages of stepper motors are that since they will move only as the controller changes the coil that is energized, the position of the motor can be known without any external feedback. Although it is possible for the motor to be turned out of phase with the coil exitation, which is know as skipping or missing steps, in most cases the reduced cost of the system is justified. Stepper motors are "brushless" unlike most other motors and so generate less EMI.

Disadvantages include lower power effeciency, higher cost per unit, and the need for a more complex drive circuit aka controller.

Control Signals: The stepper motor controller typically accepts two inputs from an external source: Step and Direction. The Direction signal set the direction of rotation and each pulse on the Step signal causes the controller to move the motor one step in that direction. The controller translates these signals into different patterns of current flow in the coils, which result in the movent of the motor.

Application: Stepper motors excel at driving loads needing up to about 100 Watts of power to move at less than a few hundred RPM with accuracy of 1/200th of a revolution. Lighter loads can be driven faster or with more accuracy. Stepper motors are commonly used to convert milling machines to CNC control.

Two phase miniature stepper motor Motor Driver