By Texas Instruments 77
Texas Instruments' DRV8805 provides an integrated solution for driving unipolar stepper motors. It includes four low-side drivers with overcurrent protection and provides built-in diodes to clamp turn-off transients generated by the motor windings. Indexer logic to control a unipolar stepper motor using a simple step/direction interface is also integrated. Three stepping modes are supported: 2 phase (full-step), 1-2 phase (half-step), and 1-phase (wave drive).