ONE-PHASE-ON FULL STEP DRIVE (WAVE DRIVE)

To make the motor take full steps, windings A and B can be

energized in the sequence

where A represents winding A energized with current in one

in the opposite direction. The motor takes one full step each

time one winding is de-energized and the other is energized.

To make the motor step in the opposite direction, the order of

the above sequence must be reversed.

Figure 7 shows the

winding currents and digital control signals for a wave drive

application of the typical application circuit.

TWO-PHASE-ON FULL STEP DRIVE

To make the motor take full steps, windings A and B can also

be energized in the sequence

and because both windings are energized at all times, this

sequence produces more torque than that produced with

wave drive. The motor takes one full step at each change of

direction of either winding current.

Figure 8 shows the wind-

ing currents and digital control signals for this application of

the typical application circuit, and

Figure 9 shows, for a

single phase, the winding current and voltage at the output of

the associated current sense amplifier.

DS011878-16

FIGURE 6. Typical Application Circuit for Driving Bipolar Stepper Motors

www.national.com

10