AN235

List of figures

Doc ID 1679 Rev 2

3/23

List of figures

Figure 1.

Stepper motor configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Figure 2.

ICs for stepper motor drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 3.

Full-step sequence for a two-phase bipolar motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 4.

Half-step sequence for a two-phase bipolar motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 5.

Current waveform to reduce half-step torque ripple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 6.

Bipolar motors deliver more torque than unipolar motors . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Figure 7.

Simple L/R drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 8.

Peak winding current decreases at higher speed, limited by motor inductance . . . . . . . . . 11

Figure 9.

L/nR drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 10.

Switch mode drive implementations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 11.

Current waveforms for L/R, L/nR and switch mode drive . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 12.

Bilevel current drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 13.

PWM current decay modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 14.

Ripple current with slow decay and fast decay mode drive . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 15.

Logic signals for full-step and half-step drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 16.

Current waveforms during transition from full-step to half-step state . . . . . . . . . . . . . . . . . 19

Figure 17.

Bipolar stepper motor drive implemented with the L6506 and the L6203. . . . . . . . . . . . . . 20

Figure 18.

Bipolar stepper motor driver implemented with the L297 and the L6203 . . . . . . . . . . . . . . 20

Figure 19.

Implementing torque ripple reduction in half-step with the L297 . . . . . . . . . . . . . . . . . . . . 21