Hardware Reference
In-Depth Information
Chapter 6
Stepper Motor
A
stepper motor
is a brushless device with multiple windings, where one rotation is
divided into several small
steps
. Stepper motors are used when precise positioning is
required. Unipolar stepper motors have multiple windings connected to a common
connection.
In this chapter, we'll recycle an old floppy-disk stepper motor. Modern stepper
motors are smaller and operate at lower voltages. This particular stepper motor presents a
good example of the challenges that exist when driving a motor from a 12 V power supply.
Floppy-Disk Stepper Motor
Figure
6-1
shows an old 5.25-inch floppy-disk stepper motor that was sitting on a shelf in
my furnace room. Perhaps you have a gem like this in your own junk box.
Figure 6-1.
A salvaged 5.25-inch floppy-disk motor
