A stepper motor driver provides precisely
controllable speed and positioning. The motor spins
at precise increments with each control pulse, easily
converting digital information to exact incremental
rotation without the need for feedback devices such
as tachometers or encoders. Because the system is open
loop, the problems of feedback loop phase shift and
resultant instability common with servo drives are eliminated.
Load characteristics, performance requirements,
and mechanical design, including coupling techniques,
must be thoroughly considered before the designer can
effectively select the most suitable motor and driver
combination for an application.